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Disclosed are several embodiments of a regenerativebraking device for an automotive vehicle. The device includes a plurality of rubber rollers (24, 26) mounted for rotation between an input shaft (14) connectable to the vehicle drivetrain and an output shaft (16) which is drivingly connected to the input shaft by a variable ratio transmission (20). When the transmission ratio is such that the input shaft rotates faster than the output shaft, the rubber rollers are torsionally stressed to accumulate energy, thereby slowing the vehicle. When the transmission ratio is such that the output shaft rotates faster than the input shaft, the rubber rollers are torsionally relaxed to deliver accumulated energy, thereby accelerating or driving the vehicle.

A combined hydraulic and regenerativebraking system and method for an electric vehicle is disclosed. The braking system is responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

A combined hydraulic and regenerativebraking system and method for an electric vehicle, with the braking system being responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

Disclosed is a regenerativebraking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

A regenerative and friction braking system for a vehicle having one or more roadwheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerativebrakes operatively connected with the roadwheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerativebraking subsystems so that maximum brake torques sustainable by the roadwheels of the vehicle without skidding or slipping will not be exceeded.

A regenerative and friction braking system for a vehicle having one or more road wheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerativebrakes operatively connected with the road wheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerativebraking subsystems so that maximum brake torques sustainable by the road wheels of the vehicle without skidding or slipping will not be exceeded. 8 figs.

An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerativebraking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.

An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerativebraking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.

In all the motor braking control systems, regenerativebraking is the only way of energy-saving braking control mode. It can convert dynamic energy which generate during braking period into electric energy, then return to the grid. In this paper, through ... Keywords: regenerativebraking, traction motor, direct torque, stator flux, slip frequency

A regenerativebraking device for an automotive vehicle includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (30) and an output shaft (32), clutches (50, 56) and brakes (52, 58) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. In a second embodiment the clutches and brakes are dispensed with and the variable ratio transmission is connected directly across the input and output shafts. In both embodiments the rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft rotates faster or relative to the output shaft and are torsionally relaxed to deliver energy to the vehicle when the output shaft rotates faster or relative to the input shaft.

An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerativebraking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerativebraking control, hydraulic braking control, and traction control. 123 figs.

An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerativebraking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerativebraking control, hydraulic braking control, and traction control.

Based on particle swarm optimization algorithm, a new fuzzy controller was constructed and a fuzzy control strategy of regenerativebraking for HEV was proposed. A model of a parallel hybrid electric vehicle was built. The performance of the default ... Keywords: hybrid electric vehicle, fuzzy control, regenerativebraking, particle swarm optimization

This work develops a method for capturing some of the kinetic energy ordinarily lost during braking on bicycles to power LED safety flashers. The system is designed to eliminate: (a) battery changing in popular LED flashers, ...

1 1 Regenerativebraking converts otherwise wasted energy from braking into electricity and stores it in the battery. In regenerativebraking, the electric motor is reversed so that, instead of using electricity to turn the wheels, the rotating wheels turn the motor and create electricity. Using energy from the wheels to turn the motor slows the vehicle down. Go to nextÂ… stage graphic: vertical blue rule Main stage: See through car with battery, engine, and electric motor visible. The car is decelerating. There are arrows flowing from the front wheels to the electric motor to the battery. Main stage: See through car with battery, engine, and electric motor visible. The car is decelerating. There are arrows flowing from the front wheels to the electric motor to the battery.

Braking button highlighted Stopped button Braking button highlighted Stopped button BRAKING PART 1 Regenerativebraking converts otherwise wasted energy from braking into electricity and stores it in the battery. In regenerativebraking, the electric motor is reversed so that, instead of using electricity to turn the wheels, the rotating wheels turn the motor and create electricity. Using energy from the wheels to turn the motor slows the vehicle down. Go to nextÂ… stage graphic: vertical blue rule Main stage: See through car with battery, engine, generator, power split device, and electric motor visible. The car is decelerating. There are arrows flowing from the front wheels to the power split device to the electric motor to the battery. Main stage: See through car with battery, engine, generator, power split device, and electric motor visible. The car is decelerating. There are arrows flowing from the front wheels to the power split device to the electric motor to the battery.

2 2 If additional stopping power is needed, conventional friction brakes (e.g., disc brakes) are also applied automatically. Go backÂ… stage graphic: vertical blue rule Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection. Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection. Battery: The battery stores energy generated from the gasoline engine or, during regenerativebraking, from the electric motor. Since the battery helps power the vehicle, it is larger and holds much more energy than batteries used to start conventional vehicles. Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection.

Sample records for regenerative braking dc from the National Library of Energy Beta (NLEBeta)

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In this paper, a braking energy recovery system based on super-capacitor was presented. The method use super-capacitor and the conventional braking resistance constitute a new braking unit to realize the regenerative energy recovery, when braking, braking ... Keywords: Urban railway transportation, regeneration braking, super-capacitor, energy recovery, electric traction

Button Stopped button highlighted subbanner graphic: gray bar Button Stopped button highlighted subbanner graphic: gray bar STOPPED When the vehicle is stopped, such as at a red light, the gasoline engine and electric motor shut off automatically so that energy is not wasted in idling. The battery continues to power auxillary systems, such as the air conditioning and dashboard displays. stage graphic: vertical blue rule Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection. Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection. Battery: The battery stores energy generated from the gasoline engine or, during regenerativebraking, from the electric motor. Since the battery helps power the vehicle, it is larger and holds much more energy than batteries used to start conventional vehicles. Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection.

Button Stopped button highlighted subbanner graphic: gray bar Button Stopped button highlighted subbanner graphic: gray bar STOPPED When the vehicle is stopped, such as at a red light, the gasoline engine and electric motor shut off automatically so that energy is not wasted in idling. The battery continues to power auxillary systems, such as the air conditioning and dashboard displays. stage graphic: vertical blue rule Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection. Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection. Battery: The battery stores energy generated from the gasoline engine or, during regenerativebraking, from the electric motor. Since the battery helps power the vehicle, it is larger and holds much more energy than batteries used to start conventional vehicles. Main stage: See through car with battery, engine, and electric motor visible. The car is stopped at an intersection.

A hybrid electric powertrain system is provided including a transmission for driving a pair of wheels of a vehicle and a heat engine and an electric motor/generator coupled to the transmission. A friction brake system is provided for applying a braking torque to said vehicle. A controller unit generates control signals to the electric motor/generator and the friction brake system for controllably braking the vehicle in response to a drivers brake command. The controller unit determines and amount of regenerative torque available and compares this value to a determined amount of brake torque requested for determining the control signals to the electric motor/generator and the friction brake system.

A mechanical gravity brake that prevents hoisted loads within a shaft from free-falling when a loss of hoisting force occurs. A loss of hoist lifting force may occur in a number of situations, for example if a hoist cable were to break, the brakes were to fail on a winch, or the hoist mechanism itself were to fail. Under normal hoisting conditions, the gravity brake of the invention is subject to an upward lifting force from the hoist and a downward pulling force from a suspended load. If the lifting force should suddenly cease, the loss of differential forces on the gravity brake in free-fall is translated to extend a set of brakes against the walls of the shaft to stop the free fall descent of the gravity brake and attached load.

Electric motorcycles are applicable to both toys and real motorcycles, and also is a reference for constructing larger electrical vehicles. A design computational model of regenerativebraking control of electric motorcycles and an experimental identification ...

A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling means causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

Energy storage systems have been designed using lightweight pressure vessels with unitized regenerative fuel cells (URFCs). The vessels provide a means of storing reactant gases required for URFCs; they use lightweight bladder liners that act as inflatable mandrels for composite overwrap and provide a permeation barrier. URFC systems have been designed for zero emission vehicles (ZEVs); they are cost competitive with primary FC powered vehicles that operate on H/air with capacitors or batteries for power peaking and regenerativebraking. URFCs are capable of regenerativebraking via electrolysis and power peaking using low volume/low pressure accumulated oxygen for supercharging the power stack. URFC ZEVs can be safely and rapidly (<5 min.) refueled using home electrolysis units. Reversible operation of cell membrane catalyst is feasible without significant degradation. Such systems would have a rechargeable specific energy > 400 Wh/kg.

This invention relates to a force measuring system capable of measuring forces associated with vehicle braking and of evaluating braking performance. The disclosure concerns an invention which comprises a first row of linearly aligned plates, a force bearing surface extending beneath and beside the plates, vertically oriented links and horizontally oriented links connecting each plate to a force bearing surface, a force measuring device in each link, a transducer coupled to each force measuring device, and a computing device coupled to receive an output signal from the transducer indicative of measured force in each force measuring device. The present invention may be used for testing vehicle brake systems.

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A gas-cooled steel skirt is used to support a refractory cored brick matrix and dome structure in a high temperature regenerative air heater useful in magnetohydrodynamic power generation. The steel skirt thermally expands to accommodate the thermal expansion of the dome structure despite substantial temperature differential thereby reducing relative movement between the dome bricks. Gas cooling of the steel skirt allows the structure to operate above its normal temperature during clean-out cycles and also allows for the control of the thermal expansion of the steel skirt.

Electrical circults for use in computers and the like are described. particularly a regenerative bistable transistor amplifler which is iurned on by a clock signal when an information signal permits and is turned off by the clock signal. The amplifier porforms the above function with reduced power requirements for the clock signal and circuit operation. The power requirements are reduced in one way by employing transformer coupling which increases the collector circuit efficiency by eliminating the loss of power in the collector load resistor.

A gas-cooled steel skirt is used to support a refractory cored brick matrix and dome structure in a high temperature regenerative air heater useful in magnetohydrodynamic power generation. The steel skirt thermally expands to accommodate the thermal expansion of the dome structure despite substantial temperature differential thereby reducing relative movement between the dome bricks. Gas cooling of the steel skirt allows the structure to operate above its normal temperature during clean-out cycles and also allows for the control of the thermal expansion of the steel skirt.

This invention consists of an efficient, high gain, compact regenerative amplifier that amplifies a seed pulse of laser energy to produce an amplified pulse of greater energy. The amplifier is useful for amplifying seed pulses having a broad bandwidth or in situations where tunability is necessary. The amplifier has high gain while maintaining high pulse contrast. A seed pulse can be amplified to the saturation fluence while maintaining a high contrast (>10[sup 3]). The regenerative amplifier has an optical cavity in a ring configuration, a gain material positioned in the cavity, a polarization-rotating element positioned in the cavity to rotate the polarization of the pulse upon each pass around the cavity, means for inserting the seed pulse into the cavity, and means for removing the polarization-rotated, amplified pulse from the cavity. In some embodiments, the seed pulse is switched in passively, by a selective polarization, and is switched out after a predetermined number of passes around the ring cavity. This completely passive arrangement avoids possibility of switchout failure, and minimizes the ASE problem. In other embodiments, a selectively actuable switch, such as electro-optic element, may be provided within the ring cavity, to switch-in the seed pulse and switch-out the amplified pulse. The electro-optic element may be actuated with a square wave that has a peak voltage equal to the half-wave voltage of the electro-optic crystal.

This invention consists of an efficient, high gain, compact regenerative amplifier that amplifies a seed pulse of laser energy to produce an amplified pulse of greater energy. The amplifier is useful for amplifying seed pulses having a broad bandwidth or in situations where tunability is necessary. The amplifier has high gain while maintaining high pulse contrast. A seed pulse can be amplified to the saturation fluence while maintaining a high contrast (>10{sup 3}). The regenerative amplifier has an optical cavity in a ring configuration, a gain material positioned in the cavity, a polarization-rotating element positioned in the cavity to rotate the polarization of the pulse upon each pass around the cavity, means for inserting the seed pulse into the cavity, and means for removing the polarization-rotated, amplified pulse from the cavity. In some embodiments, the seed pulse is switched in passively, by a selective polarization, and is switched out after a predetermined number of passes around the ring cavity. This completely passive arrangement avoids possibility of switchout failure, and minimizes the ASE problem. In other embodiments, a selectively actuable switch, such as electro-optic element, may be provided within the ring cavity, to switch-in the seed pulse and switch-out the amplified pulse. The electro-optic element may be actuated with a square wave that has a peak voltage equal to the half-wave voltage of the electro-optic crystal.

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High energy laser system using a regenerative amplifier, which relaxes all constraints on laser components other than the intrinsic damage level of matter, so as to enable use of available laser system components. This can be accomplished by use of segmented components, spatial filters, at least one amplifier using solid state or gaseous media, and separated reflector members providing a long round trip time through the regenerative cavity, thereby allowing slower switching and adequate time to clear the spatial filters, etc. The laser system simplifies component requirements and reduces component cost while providing high energy output.

High energy laser system is disclosed using a regenerative amplifier, which relaxes all constraints on laser components other than the intrinsic damage level of matter, so as to enable use of available laser system components. This can be accomplished by use of segmented components, spatial filters, at least one amplifier using solid state or gaseous media, and separated reflector members providing a long round trip time through the regenerative cavity, thereby allowing slower switching and adequate time to clear the spatial filters, etc. The laser system simplifies component requirements and reduces component cost while providing high energy output. 10 figs.

This paper presents the development of a new electromechanical brake system using magnetorheological (MR) fluid. The proposed brake system consists of rotating disks immersed in a MR fluid and enclosed in an electromagnet, where the yield stress of the ... Keywords: Automotive brake, Computational fluid dynamics, Electric brake actuator, Finite element analysis, Magnetorheological fluid, Multidisciplinary design optimization

-mail: jdixon@ing.puc.cl *University of ConcepciÃ³n Abstract An ultracapacitor bank control system and decelerations of the vehicle with minimal loss of energy, and minimal degradation of the main battery pack. The system uses an IGBT Buck-Boost converter, which is connected to the ultracapacitor bank at the Boost side

Multi-effect regenerative absorption cycles which provide a high coefficient of performance (COP) at relatively high input temperatures. An absorber-coupled double-effect regenerative cycle (ADR cycle) (10) is provided having a single-effect absorption cycle (SEA cycle) (11) as a topping subcycle and a single-effect regenerative absorption cycle (1R cycle) (12) as a bottoming subcycle. The SEA cycle (11) includes a boiler (13), a condenser (21), an expansion device (28), an evaporator (31), and an absorber (40), all operatively connected together. The 1R cycle (12) includes a multistage boiler (48), a multi-stage resorber (51), a multisection regenerator (49) and also uses the condenser (21), expansion device (28) and evaporator (31) of the SEA topping subcycle (11), all operatively connected together. External heat is applied to the SEA boiler (13) for operation up to about 500 degrees F., with most of the high pressure vapor going to the condenser (21) and evaporator (31) being generated by the regenerator (49). The substantially adiabatic and isothermal functioning of the SER subcycle (12) provides a high COP. For higher input temperatures of up to 700 degrees F., another SEA cycle (111) is used as a topping subcycle, with the absorber (140) of the topping subcycle being heat coupled to the boiler (13) of an ADR cycle (10). The 1R cycle (12) itself is an improvement in that all resorber stages (50b-f) have a portion of their output pumped to boiling conduits (71a-f) through the regenerator (49), which conduits are connected to and at the same pressure as the highest pressure stage (48a) of the 1R multistage boiler (48).

We describe a wavelength tunable alexandrite regenerative amplifier which is used to amplify nanosecond slices from a single-frequency cw dye laser or 50-ps pulses emitted by a diode laser to energies in the 10-mJ range. The amplified 5-ns slices generated by the cw-pumped line narrowed dye laser are Fourier transform limited. The 50-ps pulses emitted by a gain-switched diode laser are amplified by more than 10 orders of magnitude in a single stage.

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A method for braking a wind turbine including at least one rotor blade coupled to a rotor. The method includes selectively controlling an angle of pitch of the at least one rotor blade with respect to a wind direction based on a design parameter of a component of the wind turbine to facilitate reducing a force induced into the wind turbine component as a result of braking.

This thesis presents a justification for the study of regenerative damping, a general statement of the regenerative damping problem, and a detailed analysis of a specific proposed solution to the regenerative damping problem. Improvement in the efficiency of many physical systems is realized by the incorporation of regenerative devices, and all devices which dissipate power are candidates for investigation as regenerative systems. The viscous damper is a dissipative device which may be suitable for energy regeneration and is therefore investigated as such. Regenerative damping involves storing the power normally dissipated by a passive viscous damper. This task is accomplished by constructing a system which connects an energy storing device to the device being damped. The connecting system must efficiently transfer power from the device being damped to the storage device while simultaneously meeting the operating impedance of the storage device and producing a desired damping impedance. Many physical systems can accomplish this task, and the variable linear transmission is proposed for further investigation. Mathematical, graphical, and computer models are constructed to study the variable linear transmission. These models directly indicate the control strategies necessary to operate the device as a regenerative damper. Studies of kinematic performance and efficiency of the proposed damper indicate that a strong connection exists between the goodness of the performance of the proposed device as a damper and its efficiency. Both of these issues are directly related to the strategy used in the active control of the device.Results indicate that in its ideal state, the proposed damper exactly solves the problem of regenerative damping. For the non-ideal operation of the device, which includes the effects of system actuation dynamics, the performance looks promising but will require more investigation into optimal control strategies. Overall, the prospects for realizing regenerative damping are shown to be positive, and further investigation of this subject is encouraged.

The authors report the work conducted by the ESA-EPE Fuel Cell Engineering Team at Los Alamos National Laboratory during FY99 on regenerative fuel cell system engineering. The work was focused on the evaluation of regenerative fuel cell system components obtained through the RAFCO program. These components included a 5 kW PEM electrolyzer, a two-cell regenerative fuel cell stack, and samples of the electrolyzer membrane, anode, and cathode. The samples of the electrolyzer membrane, anode, and cathode were analyzed to determine their structure and operating characteristics. Tests were conducted on the two-cell regenerative fuel cell stack to characterize its operation as an electrolyzer and as a fuel cell. The 5 kW PEM electrolyzer was tested in the Regenerative Fuel Cell System Test Facility. These tests served to characterize the operation of the electrolyzer and, also, to verify the operation of the newly completed test facility. Future directions for this work in regenerative fuel cell systems are discussed.

A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse.

A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse. 7 figures.

An inverter topology and control scheme has been developed that can drive low-inductance, surface-mounted permanent magnet motors over the wide constant power speed range required in electric vehicle applications. This new controller is called the dual-mode inverter control (DMIC) [1]. The DMIC can drive either the Permanent Magnet Synchronous Machine (PMSM) with sinusoidal back emf, or the brushless dc machine (BDCM) with trapezoidal emf in the motoring and regenerativebraking modes. In this paper we concentrate on the BDCM under high-speed motoring conditions. Simulation results show that if all motor and inverter loss mechanisms are neglected, the constant power speed range of the DMIC is infinite. The simulation results are supported by closed form expressions for peak and rms motor current and average power derived from analytical solution to the differential equations governing the DMIC/BDCM drive for the lossless case. The analytical solution shows that the range of motor inductance that can be accommodated by the DMIC is more than an order of magnitude such that the DMIC is compatible with both low- and high-inductance BDCMs. Finally, method is given for integrating the classical hysteresis band current control, used for motor control below base speed, with the phase advance of DMIC that is applied above base speed. The power versus speed performance of the DMIC is then simulated across the entire speed range.

A regenerative frequency divider and multiplier having wide band input characteristics is presented. The circuit produces output oscillations having frequencies related by a fixed ratio to input oscillations over a wide band of frequencies. In accomplishing this end, the divider-multiplier includes a wide band input circuit coupled by mixer means to a wide band output circuit having a pass band related by a fixed ratio to that of the input circuit. A regenerative feedback circuit derives a fixed frequency ratio feedback signal from the output circuit and applies same to the mixer means in proper phase relation to sustain fixed frequency ratio oscillations in the output circuit.

In highly power constrained sensor networks, harvesting energy from the environment makes prolonged or even perpetual execution feasible. In such energy harvesting systems, energy sources are characterized as being regenerative. Regenerative energy sources ...

In this paper, methods of energy recovery for electric motors in braking mode are presented. Also for motors with low and medium regenerative power, a low cost and simple structure is proposed. In this method, for converting the high voltage of DC bus ... Keywords: bidirectional power flow, energy saving, regenerativebrake

Solar hydrogen system is a unique power system that can meet the power requirement for the energy future demand, in such a system the hydrogen used to be the energy carrier which can produced through electrolysis by using the power from the PV during ... Keywords: electrolyzer, fuel cell, hydrogen, photovoltaic, regenerative, solar hydrogen system

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A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling device causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

A thermally regenerative electrochemical system is described including an electrochemical cell with two water-based electrolytes separated by an ion exchange membrane, at least one of the electrolytes containing a complexing agent and a salt of a multivalent metal whose respective order of potentials for a pair of its redox couples is reversible by a change in the amount of the ocmplexing agent in the electrolyte, the complexing agent being removable by distillation to cause the reversal.

This is an executive summary of a final subcontract report that describes the successful completion of a closed-loop demonstration of a regenerative thermoelectromechanical device using solar heat input for the production of electricity. The full report, which contains a detailed description of the two-year effort, is currently subject to a government secrecy order which precludes public release of the information. Copies of the full report will be made available for general release whenever the secrecy order is lifted.

We compute Shannon capacity of nonlinear channels with regenerative elements. Conditions are found under which capacity of such nonlinear channels is higher than the Shannon capacity of the classical linear additive white Gaussian noise channel. We develop a general scheme for designing the proposed channels and apply it to the particular nonlinear sine-mapping. The upper bound for regeneration efficiency is found and the asymptotic behavior of the capacity in the saturation regime is derived.

THIS THESIS addresses the development of system architectures and circuit topologies for dc-dc power conversion at very high frequencies. The systems architectures that are developed are structured to overcome limitations ...

The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation. 11 figs.

The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation.

This report documents the selection and preliminary design of a new aerodynamic braking system for use on the stall-regulated AWT-26/27 wind turbines. The goal was to identify and design a configuration that offered improvements over the existing tip brake used by Advanced Wind Turbines, Inc. (AWT). Although the design objectives and approach of this report are specific to aerodynamic braking of AWT-26/27 turbines, many of the issues addressed in this work are applicable to a wider class of turbines. The performance trends and design choices presented in this report should be of general use to wind turbine designers who are considering alternative aerodynamic braking methods. A literature search was combined with preliminary work on device sizing, loads and mechanical design. Candidate configurations were assessed on their potential for benefits in the areas of cost, weight, aerodynamic noise, reliability and performance under icing conditions. As a result, two configurations were identified for further study: the {open_quotes}spoiler-flap{close_quotes} and the {open_quotes}flip-tip.{close_quotes} Wind tunnel experiments were conducted at Wichita State University to evaluate the performance of the candidate aerodynamic brakes on an airfoil section representative of the AWT-26/27 blades. The wind tunnel data were used to predict the braking effectiveness and deployment characteristics of the candidate devices for a wide range of design parameters. The evaluation was iterative, with mechanical design and structural analysis being conducted in parallel with the braking performance studies. The preliminary estimate of the spoiler-flap system cost was $150 less than the production AWT-26/27 tip vanes. This represents a reduction of approximately 5 % in the cost of the aerodynamic braking system. In view of the preliminary nature of the design, it would be prudent to plan for contingencies in both cost and weight.

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Embodiments of DC source assemblies of power inverter systems of the type suitable for deployment in a vehicle having an electrically grounded chassis are provided. An embodiment of a DC source assembly comprises a housing, a DC source disposed within the housing, a first terminal, and a second terminal. The DC source also comprises a first capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the first terminal. The DC source assembly further comprises a second capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the second terminal.

Regenerative medicine is a pioneering field aimed at restoring and regenerating the function of damaged cells, organs and tissues in order to establish normal function. It demands the cross communication of disciplines to develop effective therapeutic ...

The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and second step of compression. In the proposed system, the compressor compresses the vapor only to 50-60% of the final pressure, while the additional compression is provided by a jet device using internal potential energy of the working fluid flow. Therefore, the amount of mechanical energy required by a compressor is significantly reduced, resulting in the increase of efficiency (either COP or EER). The novelty of the cycle is in the equipment and in the way the multi-staging is accomplished. The anticipated result will be a new refrigeration system that requires less energy to accomplish a cooling task. The application of this technology will be for more efficient designs of: (1) Industrial chillers, (2) Refrigeration plants, (3) Heat pumps, (4) Gas Liquefaction plants, (5) Cryogenic systems.

In highly power constrained sensor networks, harvesting energy from the environment makes prolonged or even perpetual execution feasible. In such energy harvesting systems, energy sources are characterized as being regenerative. Regenerative energy sources fundamentally change the problem of power scheduling for embedded devices. Instead of the problem being one of maximizing the lifetime of the system given a total amount of energy, as in traditional battery powered devices, the problem becomes one of preventing energy depletion at any given time. Coupling relatively computationally intensive applications, such as video processing applications, with the constrained FPGAs that are feasible on power constrained embedded systems, makes dynamic reconfiguration essential. It provides the speed comparable to a hardware implementation, but it also allows the dynamic reconfiguration to meet the multiple application needs of the system. Different applications can be loaded on the FPGA, as the system’s needs change over time. The problem becomes how to schedule the dynamic reconfiguration to appropriately make use of the regenerative energy source, to ensure the proper availability of energy for the system over time. In this paper, we present a methodology for carrying out dynamic reconfiguration for regenerative energy sources, based on statistical analysis of tasks and supply energy. The approach is evaluated through extensive simulations. Additionally, we have evaluated our implementation on our regenerative energy, dynamically reconfigurable prototype, known as the MicrelEye. Our approach is shown to miss 57.7 % less deadlines on average than the current approach for reconfiguration with regenerative energy sources. 1.

A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

Titanium alloys are one of several candidate materials for the next generation of truck disk brake rotors. Despite their advantages of lightweight relative to cast iron and good strength and corrosion resistance, titanium alloys are unlikely to be satisfactory brake rotor materials unless their friction and wear behavior can be significantly improved. In this study, a surface engineering process oxygen diffusion was applied to titanium rotors and has shown very encouraging results. The oxygen diffused Ti-6Al-4V (OD-Ti) was tested on a sub-scale brake tester against a flat block of commercial brake lining material and benchmarked against several other Ti-based materials, including untreated Ti-6Al-4V, ceramic particle-reinforced Ti composites (MMCs), and a thermal-spray-coated Ti alloy. With respect to friction, the OD-Ti outperformed all other candidate materials under the imposed test conditions with the friction coefficient remaining within a desirable range of 0.35-0.50, even under the harshest conditions when the disk surface temperature reached nearly 600 ?C. In addition, the OD-Ti showed significantly improved wear-resistance over the non-treated one and was even better than the Ti-based composite materials.

A continuously pumped Nd:YLF regenerative amplifier has been developed that can amplify 40-psec pulses at a repetition rate of greater than 10 kHz, with an average power in excess of 5 W. Pulse energies are as high as 2.0 mJ at 3 kHz and 640 {mu}J at 10.5 kHz. The limitation on the amplifier repetition rate that is associated with piezoelectric ringing in LiNbO{sub 3} electro-optics has been overcome by using short-pulsed electric fields (10 nsec) and proper acoustic damping. Regenerative pulse amplification, limited in repetition only by the pump rate of the gain medium, has been achieved. The high repetition rate in regenerative pulse amplification made possible by this development should prove important for signal-processing considerations in a wide variety of pulse-amplification applications.

An ignition feedback regenerative amplifier consists of an injector, a linear accelerator with energy recovery, and a high-gain free electron laser amplifier. A fraction of the free electron laser output is coupled to the input to operate the free electron laser in the regenerative mode. A mode filter in this loop prevents run away instability. Another fraction of the output, after suitable frequency up conversion, is used to drive the photocathode. An external laser is provided to start up both the amplifier and the injector, thus igniting the system.

The Federal Motor Carrier Safety Administration, in coordination with the Federal Highway Administration, sponsored the Heavy and Overweight Vehicle Brake Testing (HOVBT) program in order to provide information about the effect of gross vehicle weight (GVW) on braking performance. Because the Federal Motor Carrier Safety Regulations limit the number of braking system defects that may exist for a vehicle to be allowed to operate on the roadways, the examination of the effect of brake defects on brake performance for increased loads is also relevant. The HOVBT program seeks to provide relevant information to policy makers responsible for establishing load limits, beginning with providing test data for a combination tractor/trailer. This testing was conducted on a five-axle combination vehicle with tractor brakes meeting the Reduced Stopping Distance requirement rulemaking. This report provides a summary of the testing activities, the results of various analyses of the data, and recommendations for future research. Following a complete brake rebuild, instrumentation, and brake burnish, stopping tests were performed from 20 and 40 mph with various brake application pressures (15 psi, 25 psi, 35 psi, 45 psi, 55 psi, and full system pressure). These tests were conducted for various brake conditions at the following GVWs: 60,000, 80,000, 91,000, 97,000, 106,000, and 116,000 lb. The 80,000-lb GVWs included both balanced and unbalanced loads. The condition of the braking system was also varied. To introduce these defects, brakes (none, forward drive axle, or rear trailer axle) were made inoperative. In addition to the stopping tests, performance-based brake tests were conducted for the various loading and brake conditions. Analysis of the stopping test data showed the stopping distance to increase with load (as expected) and also showed that more braking force was generated by the drive axle brakes than the trailer axle brakes. The constant-pressure stopping test data revealed a linear relationship between brake application pressure and was used to develop an algorithm to normalize stopping data for weight and initial speed.

The main idea of multi-class support vector machines (SVMs) is described. a multi-class model for regenerative water heater fault diagnosis is presented combining the fuzzy logic and SVMs. The typical faults set of regenerative water heater is built ... Keywords: steam turbine, regenerative water heater, fuzzy rules, support vector machines, fault diagnosis

The main idea of multi-class support vector machines (SVMs) is described. a multi-class model for regenerative water heater fault diagnosis is presented combining the fuzzy logic and SVMs. The typical faults set of regenerative water heater is built ... Keywords: fault diagnosis, fuzzy rules, regenerative water heater, steam turbine, support vector machines

This document was prepared to support the primary goals of the Department of Energy, Office of Heavy Vehicle Technologies. These were recently stated as follows: ''Develop by 2004 the enabling technologies for a class 7-8 truck with a fuel efficiency of 10 mpg (at 65 mph) which will meet prevailing emission standards. For Class 3-6 trucks operating on an urban driving cycle, develop by 2004 commercially viable vehicles that achieve at least double the fuel economy of comparable current vehicles (1999), and as a research goal, reduce criteria pollutants to 30% below EPA standards. Develop by 2004 the diesel engine enabling technologies to support large-scale industry dieselization of Class 1 and 2 trucks, achieving a 35 % fuel efficiency improvement over comparable gasoline-fueled trucks, while meeting applicable emissions standards.'' The enabling technologies for improving the fuel efficiency of trucks, include not only engine technologies but also technologies involved with lowering the rolling resistance of tires, reducing vehicle aerodynamic drag, improving thermal management, and reducing parasitic frictional losses in drive train components. Opportunities also exist for making better use of the energy that might ordinarily be dissipated during vehicle braking. Braking systems must be included in this evaluation since safety in truck operations is vital, and braking requirements are greater for vehicles having lowered resistance to rolling. The Office of Heavy Vehicle Technologies has initiated a program to improve the aerodynamics of heavy vehicles through wind tunnel testing, computational modeling, and on-road evaluations. That activity is described in a separate multi-year plan; therefore, emphasis in this document will be on tires, drive trains, and braking systems. Recent, dramatic fluctuations in diesel fuel prices have emphasized the importance of effecting savings in truck fuel economy by implementing new component designs and materials.

an increasingly familiar generation source and elec- tronicssource of ancillary services either to buffer local variable generation,sources, e.g. photovoltaic modules (PV), from other direct current (DC) generation,

In this paper, we develop a robust controller for parallel DC-DC converter system by combining the adaptive backstepping technique and decentralised control. The voltages and currents of all converters are coupled with each other. The parallel DC-DC ...

Zero Net Energy Buildings are increasingly being designed and constructed in response to the demand for sustainable buildings. But, we must now go beyond merely sustaining our environment for future generations we must provide regenerative designs that restore our natural environment. This paper will document the design of a regenerative high-rise tower in Shreveport, Louisiana, which will serve as a facility to train individuals in a non-profit organization’s renewal strategies and demonstrate by example the pedagogy of regenerative design. The 16-story structure — built in the 1950s and named the Petroleum Tower, reflecting the commodity that then ruled the local economy — was vacant and asbestos-laden when given to the non-profit Community Renewal International (CRI) in 2001. In 2006, funded by a grant from the U.S. Environmental Protection Agency, workers removed the asbestos. Through a follow up grant from the U.S. Department of Energy to support the design process of a new CRI headquarters building, the University of Texas at Austin School of Architecture completed architectural design studies for the building renewal. The principles of this new design include: day lighting, envelope configuration, building integrated photovoltaic systems, green surfaces, ventilation strategies, advanced mechanical cooling systems, regenerative elevator systems, energy management systems, water harvesting, grey water systems, trigeneration systems and a combined heating, hot water and power biodiesel plant.

This paper addresses some of the opportunities and the challenges in the design of multi-hop systems that utilize cooperation with one or two intermediate regenerative relays to provide high-quality communication between a source and a destination. We ...

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A compact high-power regenerative Nd-phosphate glass amplifier is described which incorporates spatial filtering and full image relay techniques. Output energies up to 1.2 J at a pulse duration of 140 +- 10 psec (FWHM) and 3 J at 900 +- 70 psec (FWHM) are achieved in a smooth nearly flattop beam intensity profile. Even with present-day technology, this system could be scaled into a terawatt regime.

We compare the existing observational data on type Ia supernovae with the evolutions of the Universe predicted by a one-parameter family of tachyon models which we have introduced recently [Phys. Rev. D 69, 123512 (2004)]. Among the set of the trajectories of the model which are compatible with the data there is a consistent subset for which the Universe ends up in a new type of soft cosmological singularity dubbed big brake. This opens up yet another scenario for the future history of the Universe besides the one predicted by the standard {lambda}CDM model.

Although conventional transformers are ac, a device that may be termed a dc transformer has been constructed by using superconductors. To provide an understanding of how such a transformer would operate, some of the properties of type I and type II superconductors ...

A system for starting an arc for welding uses three DC power supplies, a high voltage supply for initiating the arc, an intermediate voltage supply for sustaining the arc, and a low voltage welding supply directly connected across the gap after the high voltage supply is disconnected.

A system for starting an arc for welding uses three DC power supplies, a high voltage supply for initiating the arc, an intermediate voltage supply for sustaining the arc, and a low voltage welding supply directly connected across the gap after the high voltage supply is disconnected.

Dynamic Brake Assessment Dynamic Brake Assessment Purpose Conduct a proof-of-concept test to examine the feasibility of developing an on-board system to assess a vehicle's ability to stop based on typical low-pressure in-service braking events. Partnerships H.T. Hackney Company MGM Brakes Overview Funded through the Federal Motor Carrier Safety Administration's Vehicle and Roadside Operations Division Concept stemming from on the Department of Energy's Medium Truck Duty Cycle research as well as previous research conducted for the National Highway Transportation Safety Administration. Signals to be collected Real-time brake application pressure Vehicle speed and acceleration GPS location and grade information Vehicle weight (current load) Engine parameters such as RPM and torque To be conducted October 2010 -

This report describes the design of a centrifugally actuated aerodynamic-overspeed device for a horizontal-axis wind turbine. The device will meet the following criteria; (1) It will be effective for airfoil angles of attack 0{degrees} to 45{degrees}. (2) It will be stowed inside the blade profile prior to deployment. (3) It will be capable of offsetting the positive torque produced by the overall blade. (4) Hinge moments will be minimized to lower actuator loads and cost. (5) It will be evaluated as a potential power modulating active rotor-control system. A literature review of aerodynamic braking devices was conducted. Information from the literature review was used to conceptualize the most effective devices for subsequent testing and design. Wind-tunnel test data for several braking devices are presented in this report. Using the data for the most promising configuration, a preliminary design was developed for a MICON 65/13 wind turbine with Phoenix 7.9-m rotor blades.

Washington. DC,20585 Washington. DC,20585 MAY' i 1995 .- The Honorable Freeman R. Bosley, Jr. ' r City Hall 1200 Narket Street St. Louis, Missouri 63103 Dear Mayor Bosley: ,'~ ,. : !' Secretary of Energy Hazel O'Leary'has announced a new approach to'openness'in " the Department of,Energy"(DOE) and its communications with the pu~blic. In 'support of this initiative, we are pleased to forward the enclosed information rel,ated to the former Petrolite Corp. site in your jurisdiction that,performed, work for DDE or,i.ts predecessor agencies. your information, use, and retention. This information is provided for DDE's Formerly Utilized Sites Remedial Action Program is responsible for identification of sites used by DDE's predecessor agencies, determining their

' Washington, DC' ' Washington, DC' 20585 The.Honorable Don Trotter, 102' Public Square Clarksville, Tennessee '37040 '_ _' ' Dear Mayor Trotter: '. Secretary of Energy Hazel .O'Leary has announced a new the Department of Energy (DOE) and its communications support of this initiative, we are pleased to forward related to the Clarksville Foundry.& Machine Co. site approach to openness in with the publ,ic'. In " the~enclosed~information in your'jurisdiction that performed work for DOE or its predecessor'agencies. This information. is provided, for.your information, use, and retention. remedial action conservative' set of technical investigations to assure environment. If'you have any questions, please feel free~to call DrI W. Alexander Uilliams 301-427-1719 of my staff.

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An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.

Abstract—A low-voltage-swing MOSFET gate drive technique is proposed in this paper for enhancing the efficiency characteristics of high-frequency-switching dc–dc converters. The parasitic power dissipation of a dc–dc converter is reduced by lowering the voltage swing of the power transistor gate drivers. A comprehensive circuit model of the parasitic impedances of a monolithic buck converter is presented. Closed-form expressions for the total power dissipation of a low-swing buck converter are proposed. The effect of reducing the MOSFET gate voltage swings is explored with the proposed circuit model. A range of design parameters is evaluated, permitting the development of a design space for full integration of active and passive devices of a low-swing buck converter on the same die, for a target CMOS technology. The optimum gate voltage swing of a power MOSFET that maximizes efficiency is lower than a standard full voltage swing. An efficiency of 88 % at a switching frequency of 102 MHz is achieved for a voltage conversion from 1.8 to 0.9 V with a low-swing dc–dc converter based on a 0.18- m CMOS technology. The power dissipation of a low-swing dc–dc converter is reduced by 27.9 % as compared to a standard full-swing dc–dc converter. Index Terms—Buck converter, dc–dc converters, enhanced efficiency, high frequency, low power, low swing, monolithic integration, on-chip voltage conversion, parameter optimization, parasitic impedances, power dissipation modeling, power supply, reduced energy dissipation, reduced voltage swing, switching voltage regulator. I.

Power Plant Circulating Water (PPCW) waste heat recycling is an important way of increasing a power plant’s primary energy ratio. According to the PPCW waste heat regenerative thermal system, the authors propose two modes of heat pump heat regenerative ... Keywords: heat pump, power plant circulating water (PPCW), waste heat recycling, energy saving

Many user facilities such as synchrotron light sources and free electron lasers require accelerating structures that support electric fields of 10-100 MV/m, especially at the start of the accelerator chain where ceramic insulators are used for very high gradient DC guns. These insulators are difficult to manufacture, require long commissioning times, and have poor reliability, in part because energetic electrons bury themselves in the ceramic, creating a buildup of charge and causing eventual puncture. A novel ceramic manufacturing process is proposed. It will incorporate bulk resistivity in the region where it is needed to bleed off accumulated charge caused by highly energetic electrons. This process will be optimized to provide an appropriate gradient in bulk resistivity from the vacuum side to the air side of the HV standoff ceramic cylinder. A computer model will be used to determine the optimum cylinder dimensions and required resistivity gradient for an example RF gun application. A ceramic material example with resistivity gradient appropriate for use as a DC gun insulator will be fabricated by glazing using doping compounds and tested.

>/gGq ' >/gGq ' ,, ' .. Department of Edgy Washington, DC,20585 ,I ' , APR 0 4 1995 The Honorable Patrick Ungaro 26 S. Phelps Street Youngstown, Ohio 44503 .' Dear );layor.Ungaro: Secretary of'Energy Hazel O'Leary has announced a new approach to openness in the Oepartment of Energy (DOE) and its coannunications with the public. In support of this initiative, we are pleased to forward the,enclosed information related to the former Ajax-Hagnethermic C,orp. site in your jurisdiction that performed work for DOE's predecessoragencies. This information is~provided for your information, use, and retention. DOE's Formerly Utilized Sites Remedial Action Program is responsible for identificationof sites used by DOE's predecessor agencies, determining their current radiological condition and, where it has authority, performing-

Future scientists advance to national Future scientists advance to national level April 3, 2012 Science Bowl winners represent NM in Washington, D.C. A team from Los Alamos bested 39 other teams from around New Mexico in the 10- hour New Mexico Regional Science Bowl, held recently at Albuquerque Academy. The team went on to represent New Mexico in the 22nd Annual Department of Energy (DOE) National Science Bowl. In addition to their travel expenses, the team also won $5,000 for their school. The team consists of students, Alexander Wang, Micha Ben-Naim, Scott Carlsten, Lorenzo Venneri and Kevin Gao, and Coach, Paolo Venneri. - 2 - Albuquerque Academy took second place and La Cueva High School in Albuquerque placed third in the "Jeopardy!"-style event. During the competition, students are asked

A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

A diode-pumped Nd:YLF regenerative amplifier (regen) has been developed and is in use in the 60-beam, 30-kJUV OMEGA laser system's driver line. The high stability, compactness, and reliability of this all-solid-state modular design are the key features of this concept. Stable, millijoule-level output-pulse energies with an overall gain of 109 have been demonstrated.

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Energy storage systems with extremely high specific energy (>400 Wh/kg) have been designed that use lightweight tankage to contain the gases generated by reversible (unitized) regenerative fuel cells (URFCs). Lawrence Livermore National Laboratory (LLNL) will leverage work for aerospace applications supported by other sponsors (including BMDO, NASA, and USAF) to develop URFC systems for transportation and utility applications. Lightweight tankage is important for primary fuel cell powered vehicles that use on-board storage of hydrogen. Lightweight pressure vessels with state-of-the-art performance factors were designed, and prototypes are being fabricated to meet the DOE 2000 goals (4000 Wh/kg, 12% hydrogen by weight, 700 Wh/liter, and $20/kWh in high volume production). These pressure vessels use technologies that are easily adopted by industrial partners. Advanced liners provide permeation barriers for gas storage and are mandrels for composite overwrap. URFCs are important to the efficient use of hydrogen as a transportation fuel and enabler of renewable energy. H{sub 2}/halogen URFCs may be advantageous for stationary applications whereas H{sub 2}/O{sub 2} or H{sub 2}/air URFCs are advantageous for vehicular applications. URFC research and development is required to improve performance (efficiency), reduce catalyst loading, understand engineering operation, and integrate systems. LLNL has the experimental equipment and advanced URFC membrane electrode assemblies (some with reduced catalyst loading) for evaluating commercial hardware (not funded by DOE in FY1999).

Regular-density silica gel is identified as the candidate desiccant for regenerative dehumidification of humid air operating at low-regeneration temperatures and high-process humidities. The literature on the equilibrium sorption uptake of water vapor by R. D. silica gel is reviewed in this work, and a large number of experimental sorption data is collected from various technical reports. The Dubinin-Polanyi sorption theory for microporous adsorbents is discussed and applied to the sorptive data. A graphical presentation of the experimental data establishes the characteristic curve for the sorption of water vapor on silica gel. The Dubinin-Astakhov correlation is used to represent the equilibrium sorption isotherm and values for the characteristic sorption energies are determined by curve fitting with the experimental data. An accurate, generalized isotherm equation for the sorption of water vapor on regular density silica gel is presented in the first part of this work. The second part of this work presents an analytical and experimental investigation of the transient heat and mass transfer in laminar flow of humid air over a silica gel surface. Experimental results are presented for the transient response of a parallel-plate dehumidifier matrix in single-blow type experiments.

A resistive, thyristor-controlled brake is used to damp transient torques in large thermo-electric generators supplying series-compensated transmission lines. Emphasis is placed on developing a suitable control algorithm and testing the algorithm through a wide variety of different operating configurations. Discrete-level Generalized Predictive Control is examined as one possible approach to optimal control of the brake. Some problems with implementation of GPC on the system are discussed. Prony analysis is used to identify system transfer functions which are then related to control design considerations and robustness properties.

A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current.

A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current. 1 fig.

programs to which it gave almost always global solutions and proved to be more robust ... In this paper, we consider DC programming with subanalytic data. .... open ball with the center x ? Rn and radius ? > 0 is denoted by B(x, ?); while the unit ... and C ? Rn is a nonempty convex set, we can equivalently transform it into a.

A technical and economic feasibility study of HVDC systems without converter transformers is presented. The presentation includes proposed solutions to the drawback related to the absence of galvanic separation between the ac and dc systems, if the converter transformers are eliminated. The results show that HVDC systems without converter transformers are both technically and economically feasible. The cost savings can be substantial.

A power generation system configured to provide direct current (DC) power to a DC link is described. The system includes a first power generation unit configured to output DC power. The system also includes a first DC to DC converter comprising an input section and an output section. The output section of the first DC to DC converter is coupled in series with the first power generation unit. The first DC to DC converter is configured to process a first portion of the DC power output by the first power generation unit and to provide an unprocessed second portion of the DC power output of the first power generation unit to the output section.

We constructed a Ti:Sapphire narrow-band regenerative amplifier as the probe laser of the experiment of momentum imaging spectroscopy of lithium dimer. The spectral profile of the regenerative cavity was designed by three birefringent filters and a plate of etalon. With 1.1-mJ pumping by the second harmonics of Nd:YLF laser, mode-locked seed pulses were amplified to {approx}25 {mu}J at 1-kHz repetition, with the bandwidth of {approx}0.7 cm{sup -1}.

We describe a method for the generation of readily synchronizable, near-transform-limited, 1064-nm, 6-mJ pulses with {lt}20-ps duration at a repetition rate of 20 Hz. The method employs chirped pulse amplification of spectrally broadened and temporally stretched pulses from a cw mode-locked Nd:YAG laser in a commercial Nd:YAG regenerative amplifier followed by pulse compression with a grating pair. Linear amplification subsequent to regenerative amplification is not required with this method, although higher energies would be easily obtained. {copyright} 1997 Optical Society of America

Catalog of DC Appliances and Power Systems Catalog of DC Appliances and Power Systems Title Catalog of DC Appliances and Power Systems Publication Type Report LBNL Report Number LBNL-5364E Year of Publication 2011 Authors Garbesi, Karina, Vagelis Vossos, and Hongxia Shen Document Number LBNL-5364E Date Published October Publisher Lawrence Berkeley National Laboratory Abstract This document catalogs the characteristics of current and potential future direct current (DC) products and power systems. It is part of a larger U.S. Department of Energy-funded project, "Direct-DC Power Systems for Energy Efficiency and Renewable Energy Integration with a Residential and Small Commercial Focus". That project is investigating the energy-savings potential, benefits, and barriers of using DC generated by on-site renewable energy systems directly in its DC form, rather than converting it first to alternating current (AC) for distribution to loads. Two related reports resulted from this work: this Catalog and a companion report that addresses direct-DC energy savings in U.S. residential buildings.Interest in 'direct-DC' is motivated by a combination of factors: the very rapid increase in residential and commercial photovoltaic (PV) power systems in the United States; the rapid expansion in the current and expected future use of energy efficient products that utilize DC power internally; the demonstrated energy savings of direct-DC in commercial data centers; and the current emergence of direct-DC power standards and products designed for grid-connected residential and commercial products. Based on an in-depth study of DC appliances and power systems, we assessed off-grid markets for DC appliances, the DC compatibility of mainstream electricity end-uses, and the emerging mainstream market for direct-DC appliances and power systems.

The environmental effects of dc overhead transmission lines are examined. The major effects of ac and dc transmission lines are compared. Dc lines have advantages compared to ac lines in terms of electrical safety for people under the lines, biological effects, corona losses, and clearance width.

An increasing number of appliances now operate on DC and providing uninterrupted power supply (UPS) to them through outages requires two conversions: first from an energy store, typically a DC battery, to AC mains and then from AC mains to the DC input ... Keywords: DC picogrid, conversion losses, power source identification

This work presents a High-Voltage Low-Power CMOS DC-DC buck regulator for automotive applications. The overall system, including the high and low voltage analog devices, the power MOS and the low voltage digital devices, was realized in the Austriamicrosystems ... Keywords: DC-DC regulator, buck converter, current control, low quiscent current, pulse frequency modulation

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This simulator experiment is a preliminary study examining the effects of different auditory signals on braking force and reaction time in a rear-end collision warning system. A driving simulator was built in which subjects operated a computer driving game. Superimposed on the game screen was the image of a car which appeared to the driver to be ahead of him/her. The image enlarged in size, appearing to be a car applying its brakes. The participant was instructed to react as he would in a real driving situation by applying his/her brakes. Closing velocities of 10 miles per hour and 30 miles per hour were used. Braking times and forces were measured for four different warning sounds: 1) no warning; 2) a pulsed warning sound that increased in repetition rate; 3) a sound that increased in frequency; and, 4) a sound that increased in intensity. Results suggested that an auditory warning signal would decrease reaction time and increase maximum braking force applied. The sound that increased in frequency and the sound that increased in intensity provided the greatest savings in reaction time, approximately one quarter second, when compared to the no warning condition. The pulsed warning sound provided the greatest increase in braking force. Participants preferred the pulsed sound over the other warning sounds. Further research must be done to determine if the warning sounds decrease the reaction time enough to cause a significant reduction in accidents.

The collapse and fragmentation of initially prolate and oblate, magnetic molecular clouds is calculated in three dimensions with a gravitational, radiative hydrodynamics code. The code includes magnetic field effects in an approximate manner: magnetic pressure, tension, braking, and ambipolar diffusion are all modelled. The parameters varied for both the initially prolate and oblate clouds are the initial degree of central concentration of the radial density profile, the initial angular velocity, and the efficiency of magnetic braking (represented by a factor $f_{mb} = 10^{-4}$ or $10^{-3}$). The oblate cores all collapse to form rings that might be susceptible to fragmentation into multiple systems. The outcome of the collapse of the prolate cores depends strongly on the initial density profile. Prolate cores with central densities 20 times higher than their boundary densities collapse and fragment into binary or quadruple systems, whereas cores with central densities 100 times higher collapse to form single...

According to the characteristic of the compressed air dryer located at the same place with the air compressor, for the large capacity thermal regenerative compressed air dryer that the absorbent is regenerated by an electric heater, this thesis puts ... Keywords: Compressed air dryer, Regeneration, Heater, Residual heat, Energy saving

We evaluate the performance of a novel 10-Hz picosecond Nd:YAG regenerative amplifier configured as a self-filtering unstable resonator. Pulse energies of approx.60 mJ in approx.100 psec at 1.06 ..mu..m are achieved using a single 6-mm-diameter Nd:YAG rod, while mode-matching requirements are minimized.

This interim report covers the second year of research on the CCURB (Corrosion Control Using Regenerative Biofilms) project. This work seeks solutions to corrosion through the use of protective biofilms. To this end, the team has studied the use of both natural and genetically-engineered bacteria for corrosion inhibition of mild steel, aluminum, brass, and copper.

Integration and Dynamics of a Renewable Regenerative Hydrogen Fuel Cell System by Alvin Peter Cell System by Alvin Peter Bergen B.A.Sc., University of Victoria, 1994 M.Sc., University of University, hydrogen and electricity storage, and fuel cells. A special design feature of this test bed is the ability

A large number of gearbox failures have occurred in the wind industry in a relatively short period, many because service loads were underestimated. High-torque transients that occur during starting and stopping are difficult to predict and may be overlooked in specifying gearbox design. Although these events comprise a small portion of total load cycles, they can be the most damaging. The severity of these loads varies dramatically with the specific configuration of the wind turbine. The large number of failures in Danish-designed Micon 65 wind turbines prompted this investigation. The high-speed and low-speed shaft torques were measured on a two-stage helical gearbox of a single Micon 65 turbine. Transient events and normal running loads were combined statistically to obtain a typical annual load spectrum. The pitting and bending fatigue lives of the gear teeth were calculated by using Miner's rule for four different high-speed shaft brake configurations. Each breaking scenario was run for both a high- and a low-turbulence normal operating load spectrum. The analysis showed increases in gear life by up to a factor of 25 when the standard high-speed shaft brake is replaced with a dynamic brake or modified with a damper. 9 refs., 9 figs., 3 tabs.

A large number of gearbox failures have occurred in the wind industry in a relatively short period, many because service loads were underestimated. High-torque transients that occur during starting and stopping are difficult to predict and may be overlooked in specifying gearbox design. Although these events comprise a small portion of total load cycles, they can be the most damaging. The severity of these loads varies dramatically with the specific configuration of the wind turbine. The large number of failures in Danish-designed Micon 65 wind turbines prompted this investigation. The high-speed and low-speed shaft torques were measured on a two-stage helical gearbox of a single Micon 65 turbine. Transient events and normal running loads were combined statistically to obtain a typical annual load spectrum. The pitting and bending fatigue lives of the gear teeth were calculated by using Miner's rule for four different high-speed shaft brake configurations. Each breaking scenario was run for both a high- and a low-turbulence normal operating load spectrum. The analysis showed increases in gear life by up to a factor of 25 when the standard high-speed shaft brake is replaced with a dynamic brake or modified with a damper. 9 refs., 9 figs., 3 tabs.

We apply population synthesis techniques to calculate the present day number of two types of white dwarf-main sequence star (WDMS) binaries within the cataclysmic variable period gap. The first are post-common envelope binaries with secondary stars that have masses between 0.17 and 0.36 Msun (gPCEBs), such that they will commence mass transfer within the period gap. The second type are systems that were CVs at some point in their past, but detached once they evolved down in orbital period to ~3 h as a consequence of disrupted magnetic braking, and are crossing the period gap via gravitational radiation (dCVs). Full population synthesis calculations are performed where we assume either constant, global values of the common envelope ejection efficiency, or consider the ejection efficiency as a function of secondary mass. Several forms of magnetic braking are also considered. We predict an excess of dCVs over gPCEBs within the period gap of ~4 to ~13 assuming an ejection efficiency between 0.1 and 0.6, and a flat initial mass ratio distribution. This excess is revealed as a prominent peak at the location of the period gap in the orbital period distribution of the combined gPCEB and dCV population. We suggest that if such a feature is observed in the orbital period distribution of an observed sample of short orbital period WDMS binaries, this would strongly corroborate the disruption of magnetic braking.

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DC Distribution: The Power To Change Buildings DC Distribution: The Power To Change Buildings Speaker(s): Brian Patterson Dennis Symanski Liang Downey Date: July 14, 2011 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Chris Marnay This seminar presents an overview of the effort to create new applications standards to drive the distribution and use of native direct current (dc) in net zero energy commercial and residential buildings. From the early days of electric power generation, distribution and use there's been a debate over which form of power, AC or DC, is best. Edison set the stage for this argument in the late 1800's with his invention of DC powered lighting systems. Tesla's system of AC dynamos, transformers and motors all but stopped the growing use of DC by the turn of the century. With the

This article is a case history of the installation of active dc filters for high-performance, low-cost harmonics filtering at the Lindome converter station in the Konti-Skan 2 HVDC transmission link between Denmark and Sweden. The topics of the article include harmonics, interference, and filters, Lindome active dc filter, active dc filter design, digital signal processor, control scheme, protection and fault monitoring, and future applications.

The use of radio-frequency (RF) amplifier topologies in dc/dc power converters allows the operating frequency to be increased by more than two orders of magnitude over the frequency of conventional converters. This enables ...

This thesis presents a new topology for a high efficiency dc/dc resonant power converter that utilizes a resistance compression network to provide simultaneous zero voltage switching and near zero current switching across ...

High frequency power conversion is attractive for the opportunities it affords for improved performance. Dc-dc converters operating at high frequencies use smaller-valued energy storage elements, which tend to be physically ...

Instrument-limited suppression of out-of-band amplified spontaneous emission (ASE) is demonstrated for the first time in a Nd:YLF diode-pumped regenerative amplifier using a volume Bragg grating (VBG) as a cavity mirror.

This is an executive summary of a final subcontract report that describes the successful completion of a closed-loop demonstration of a regenerative thermoelectromechanical device using solar heat input for the production of electricity. The full report, which contains a detailed description of the two-year effort, is currently subject to a government secrecy order which precludes public release of the information. Copies of the full report will be made available for general release whenever the secrecy order is lifted.

This paper presents the methodology developed for the estimation of thermodynamic performance and reports the optimum cycle parameters of coal fired CCGT in regenerative and combined cycle configurations using air, helium and carbon dioxide as working gases. A rigorous approach has been followed for the determination of the cycle efficiency by assuming the specific heat of working gases as a continuous function of temperature for accurate estimation of cycle parameters. 14 refs.

Spiral plate heat exchangers as adsorbers have been proposed, and a prototype heat regenerative adsorption refrigerator using activated carbon-methanol pair has been developed and tested. Various improvements have been made, the authors get a specific cooling power for 2.6 kg-ice/day-kg adsorbent at the condition of generation temperature lower than 100 C. Discussions on the arrangements of thermal cycles and influences of design are shown.

A high voltage DC power supply having a first series resistor at the output for limiting current in the event of a short-circuited output, a second series resistor for sensing the magnitude of output current, and a voltage divider circuit for providing a source of feedback voltage for use in voltage regulation is disclosed. The voltage divider circuit is coupled to the second series resistor so as to compensate the feedback voltage for a voltage drop across the first series resistor. The power supply also includes a pulse-width modulated control circuit, having dual clock signals, which is responsive to both the feedback voltage and a command voltage, and also includes voltage and current measuring circuits responsive to the feedback voltage and the voltage developed across the second series resistor respectively. 7 figs.

jpfl.3%2' jpfl.3%2' ) .,Departhent of Eikrgj! : Washington, DC~ZO585 .-, , , Lf; I: ~.1,' .Yj4 , The Honorable Louis Barlup 55 ,E. Main Street Waynesboro;,Pennsy,lvania 17268 '~ Dear Mayor Barl,up:' Secretary of Energy Hazel O'Leary has'announced' a new approach to openness,in the Department of Energy-(DOE) and its communications with the public. In support-of this initiative, we are pleased.to forward the enclosed information related to the former Landis Machine Tool Co. site in your jurisdiction that performed work for DOE or its predecessor agencies. This information:is provided for your information< use, and retention. DOE's Formerly Utilized Sites Remedial Action Program is responsible for identification of sites used by DOE's predecessor agencies, determining their

Concepts and technologies described herein provide for an accurate and cost-effective method for rotating a solar array disk for tracking the movement of the sun. According to various aspects, a motor includes a fixed caliper and a translating caliper positioned adjacent to one another. Electromagnetically controlled brakes on the translating caliper grip the solar array disk while adjacent, but spaced apart, electromagnets on the fixed caliper and the translating caliper are energized to create an attractive force that pulls the translating caliper with the solar array disk toward the fixed caliper. After reaching the fixed caliper, brakes on the fixed caliper are engaged with the disk, brakes on the translating caliper are released from the disk, and the translating caliper is pushed back to the starting location where the process repeats until the desired rotation is completed.

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based on eddy current brakes because they are inexpensive, friction- e-mail: andrewg@cim.mcgill.ca e-mail: champ@cim.mcgill.ca e-mail: hayward@cim.mcgill.ca free, capable of fast turn-on time, and linear

In this paper, we propose CityCarControl, a system to manage the steering, braking, and throttle of a new class of intra-city electric vehicles. These vehicles have a focus on extreme light-weight and a small parking ...

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3 Aerial view of Washington D.C. 3 Aerial view of Washington D.C. News From the D.C. Office The federal government is the largest single purchaser in the world for many energy-related products. Federal buying power-along with that of state and local agencies-represents a largely untapped resource to increase the energy efficiency of consumer products and commercial equipment. LBL is helping the DOE Federal Energy Management Program (FEMP) develop and lead a government-wide initiative to capture this market-transforming opportunity. Jeff Harris and others in LBL's D.C. office are heading FEMP's efforts to identify how future federal purchases can be more energy-efficient. The U.S. government spends more than $70 billion a year to purchase supplies and equipment, of which an estimated $10-20 billion are energy-

Societal concerns on combustion-based fuel consumption are ever-increasing. With respect to internal combustion engines, this translates to a need to increase brake fuel conversion efficiency (BFCE). Diesel engines are a relatively efficient internal combustion engine to consider for numerous applications, but associated actions to mitigate certain exhaust emissions have generally deteriorated engine efficiency. Conventionally, diesel engine emission control has centered on in-cylinder techniques. Although these continue to hold promise, the industry trend is presently favoring the use of after-treatment devices which create new opportunities to improve the diesel engine's brake fuel conversion efficiency.
This study focuses on injection timing effects on the combustion processes, engine efficiency, and the engine system's responses. The engine in the study is a medium duty diesel engine (capable of meeting US EPA Tier III off road emission standards) equipped with common rail direct fuel injection, variable geometry turbo charging, and interfaced with a custom built engine controller. The study found that injection timing greatly affected BFCE by changing the combustion phasing. BFCE would increase up to a maximum then begin to decrease as phasing became less favorable. Combustion phasing would change from being mostly mixing controlled combustion to premixed combustion as injection timing would advance allowing more time for fuel to mix during the ignition delay. Combustion phasing, in turn, would influence many other engine parameters. As injection timing is advanced, in-cylinder temperatures and pressures amplify, and intake and exhaust manifold pressures deteriorate. Rate of heat release and rate of heat transfer increase when injection timing is advanced. Turbocharger speed falls with the advancing injection timing. Torque, however, rose to a maximum then fell off again even though engine speed and fueling rate were held constant between different injection timings. Interestingly, the coefficient of heat transfer changes from a two peak curve to a smooth one peak curve as the injection timing is advanced further. The major conclusion of the study is that injection advance both positively and negatively influences the diesel engine's response which contributes to the brake fuel conversion efficiency.

This report documents a field demonstration performed at Bowling Green State University (BGSU) as part of an Electric Power Research Institute (EPRI) research project on improving the economics of photovoltaic (PV) power generation with innovative direct current (dc) applications. Unlike conventional dc uses for PV energy, this project aimed to demonstrate the powering of specific loads in grid-connected buildings without interference to the ac distribution system or other building loads.

The IMPRESS is a significant advancement in space system technology as it is able to operate alternately as a fuel cell to produce electrical power from stored hydrogen and oxygen and as a water electrolyzer using electrical power to produce hydrogen and oxygen from stored water. The electrolysis of a controllable fraction of stored water can provide high Isp rocket propellants on demand. The heart of the IMPRESS is the Unitized Regenerative Fuel Cell (URFC), which produces power and electrolytically regenerates its reactants using a single stack of reversible cells. This integrated approach has several significant advantages over separate (battery) power and propulsion systems.

An advanced absorption refrigeration cycle was proposed as a heat-activated refrigeration system. Referred to as the double-effect regenerative absorption cycle of cycle 2R, it improves the performance of the conventional single-effect absorption cycle at high heat source temperatures. The performance of cycle 2R continually improves as input temperatures rise, in contrast to the conventional double-effect absorption cycle that has a sharp cut-off temperature below which it ceases to operate. Cycle 2R operates with two subcycles, the first-effect and the second-effect subcycles.

In this paper, an overview of DC micro-grid is described, which includes the status of DC micro-grid protection and its future development. The paper presents the key techniques of DC micro-grid protection. So far, standards, guidelines and techniques ... Keywords: DC micro-grid, protection, protective devices, structures, technological gaps

The nature of foot movement time (MT) in an actual braking maneuver and in a stationary vehicle was investigated regarding the effects of age and gender of the driver and nature of the stimulus to which the driver was responding. ANOVAs showed that the nature of the stimulus was not a significant factor in length of MT, but distance between pedals and age-gender levels were found to have significant effects. For the actual braking maneuver, gender and the gender-by-age interaction were significant; in the stationary vehicle portion of the study, they were not. Mean foot MT for both genders over all conditions were 0.28 seconds for women and 0.22 seconds for men. For older drivers, over all conditions, the mean foot MT was 0.25 seconds, and, for the younger drivers, 0.24 seconds. Linear regressions revealed high intra-subject variation in MT, which was corroborated by comparing with data from other parts of the study. Poor r2 values for fitting the data to Fitts' Law and to a modification of Fitts' Law were attributed to this high intra-subject variation and to obtaining data from only two different movement amplitudes. It was found that drivers' foot MTs tended to converge to a common value when controlling the vehicle at 88 km/hr (55 mph) as opposed to sitting in the driver's seat while the vehicle was stationary; mean foot MT for each subject group decreased, and differences between genders and age groups significantly diminished while the car was in motion.

At present, there are basically three different systems for converting energy in geothermal fluid into power: vapor-flashing system, total flow system, and binary system. A comparison of the power production processes was made on the basis of work output in Kwh per 1000 pounds of geothermal fluid for self flowing wells with wellhead pressure of 100 psia and for wells with downhole pumps. For simplicity, the assumptions were made that the enthalpy of the geothermal fluid in the reservoir is approximately equal to that at the wellhead, that the thermodynamic properties of geothermal fluid may be approximated by those of water, and that the pressure effects on the properties of fluid are negligible. The results showed that the performance of the two-stage vapor-flashing system is not appreciably improved by using a downhole pump. The total flow system is simple, but its success depends mainly on the development of a reliable machine with sufficiently high thermal efficiency. The regenerative isobutane system is impractical, if the geothermal fluid temperature is below 380/sup 0/F. But, when the brine temperatures range from 485 to 600/sup 0/F, the regenerative isobutane system with downhole pump exhibits superior performance as compared to two-stage vapor-flashing system, basic isobutane system, or total flow system.

Washington, DC has a unique urban form that is the result of a century-old law. Through the narrow lens of DC's height limit, I survey a range of topics related to urban height, starting with a review of its history of ...

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Road vehicles can expend a significant amount of energy in undesirable vertical motions that are induced by road bumps, and much of that is dissipated in conventional shock absorbers as they dampen the vertical motions. Presented in this paper are some of the results of a study aimed at determining the effectiveness of efficiently transforming that energy into electrical power by using optimally designed regenerative electromagnetic shock absorbers. In turn, the electrical power can be used to recharge batteries or other efficient energy storage devices (e.g., flywheels) rather than be dissipated. The results of the study are encouraging - they suggest that a significant amount of the vertical motion energy can be recovered and stored.

An all-solid-state tunable diode-pumped Cr{sup 3+}:LiSrAlF{sub 6} (Cr:LiSAF) regenerative amplifier, seeded by a tunable diode-pumped Cr:LiSAF femtosecond oscillator, has been demonstrated for the first time to our knowledge. The oscillator was tunable over 75 nm and generated pulses as short as 24 fs. As much as 70 mW average output power was obtained with pulses of 40-fs duration. The amplifier produced recompressed pulses of less than 200-fs duration with energies exceeding 1{mu}J at a repetition rate as high as 25 kHz. {copyright} {ital 1995} {ital Optical} {ital Society} {ital of} {ital America}.

GRIDS Project: Proton Energy Systems is developing an energy storage device that converts water to hydrogen fuel when excess electricity is available, and then uses hydrogen to generate electricity when energy is needed. The system includes an electrolyzer, which generates and separates hydrogen and oxygen for storage, and a fuel cell which converts the hydrogen and oxygen back to electricity. Traditional systems use acidic membranes, and require expensive materials including platinum and titanium for key parts of the system. In contrast, Proton Energy Systems’ new system will use an inexpensive alkaline membrane and will contain only inexpensive metals such as nickel and stainless steel. If successful, Proton Energy Systems’ system will have similar performance to today’s regenerative fuel cell systems at a fraction of the cost, and can be used to store electricity on the electric grid.

A coal combustor/gasifier is disclosed which produces a low or medium combustion gas fired furnances or boilers. Two concentric shells define a combustion air flows to provide regenerative cooling of the inner shell for dry ash operation. A fuel flow and a combustion air flow having opposed swirls are mixed and burned in a mixing-combustion portion of the combustion volume and the ash laden combustion products flow with a residual swirl into an ash separation region. The ash is cooled below the fusion temperature and is moved to the wall by centrifugal force where it is entrained in the cool wall boundary layer. The boundary layer is stabilized against ash re-entrainment as it is moved to an ash removal annulus by a flow of air from the plenum through slots in the inner shell, and by suction on an ash removal skimmer slot.

A new configuration of DC motor/generator is based on a Halbach array of permanent magnets. This motor does not use ferrous materials so that the only losses are winding losses and losses due to bearings and windage. An ``inside-out`` design is used as compared to a conventional motor/generator design. The rotating portion, i.e., the rotor, is on the outside of the machine. The stationary portion, i.e., the stator, is formed by the inside of the machine. The rotor contains an array of permanent magnets that provide a uniform field. The windings of the motor are placed in or on the stator. The stator windings are then ``switched`` or ``commutated`` to provide a DC motor/generator much the same as in a conventional DC motor. The commutation can be performed by mechanical means using brushes or by electronic means using switching circuits. The invention is useful in electric vehicles and adjustable speed DC drives. 17 figs.

A new configuration of DC motor/generator is based on a Halbach array of permanent magnets. This motor does not use ferrous materials so that the only losses are winding losses and losses due to bearings and windage. An "inside-out" design is used as compared to a conventional motor/generator design. The rotating portion, i.e., the rotor, is on the outside of the machine. The stationary portion, i.e., the stator, is formed by the inside of the machine. The rotor contains an array of permanent magnets that provide a uniform field. The windings of the motor are placed in or on the stator. The stator windings are then "switched" or "commutated" to provide a DC motor/generator much the same as in a conventional DC motor. The commutation can be performed by mechanical means using brushes or by electronic means using switching circuits. The invention is useful in electric vehicles and adjustable speed DC drives.

The goal of this project is to develop and fabricate a 5kW dc-dc converter with a baseline 14V output capability for fuel cell and hybrid vehicles. The major objectives for this dc-dc converter technology are to meet: Higher efficiency (92%); High coolant temperature,e capability (105 C); High reliability (15 Years/150,000miles); Smaller volume (5L); Lower weight (6kg); and Lower cost ($75/kW). The key technical challenge for these converters is the 105 C coolant temperatures. The power switches and magnetics must be designed to sustain these operating temperatures reliably, without a large cost/mass/volume penalty.

A power distribution scheme based on the use of on-board DC-DC converters is proposed to efficiently distribute power to the on-detector electronics of SLHC trackers. A comparative analysis of different promising converter topologies is presented, leading to the choice of a magneticbased buck converter as a first conversion stage followed by an on-chip switched capacitors converter. An overall efficiency above 80% is estimated for the practical implementation proposed.

EPRI developed a fact charging technology for electric vehicles based on a solid state transformer technology known as the Intelligent Universal Transformer (IUT). The IUT technology replaces both the independent power conversion units as well as the conventional transformer with a single interface system which can be used for fast charging of electric vehicles. The versatility of the IUT provides an intermediate DC bus voltage at the 400-V level that can be directly used for a DC distribution ...

The delivery of power is considered to be one of the major challenges for the upgrade of the CMS silicon strip tracker for SLHC. The inevitable increase in granularity and complexity of the device is expected to result in a power consumption comparable or even higher than the power consumption of todays' strip tracker. However, the space available for cables will remain the same. In addition, a further increase of the tracker material budget due to cables and cooling is considered inacceptable, as the performance of the CMS detector must not be compromised for the upgrade. Novel powering schemes such as serial powering or usage of DC-DC converters have been proposed to solve the problem. To test the second option, substructures of the current CMS silicon strip tracker have been operated for the first time with off-the-shelf DC-DC buck converters as well as with first prototypes of custom-designed DC-DC converters. The tests are described and the results are discussed.

: In this lab we will develop and validate a basic model of a permanent magnet DC motor (Yaskawa Electric MINI'll discuss a permanent magnet DC motor whose stator consists of a permanent magnet. In this case, we can take in the empty blocks. Figure 2: A block diagram of a permanent magnet DC motor. Prelab Questions: 1) From your

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A constant-frequency peak current mode synchronous step-down DC-DC controller integrated circuit has been designed with adaptive dead-time control. The adaptive dead-time control circuitry is implemented as digital ...

This paper presents a fully integrated on-chip switched-capacitor (SC) DC-DC converter that supports two regulated power supply voltages of 2.2V and 3.2V from 5V input supply and delivers the maximum load currents up to 8mA at both of the outputs. The ... Keywords: dc-dc converter, dual output, switched-capacitor

11 Federal Register 11 Federal Register / Vol. 76, No. 122 / Friday, June 24, 2011 / Notices 888 First Street, NE., Washington, DC 20426. The filings in the above-referenced proceeding are accessible in the Commission's eLibrary system by clicking on the appropriate link in the above list. They are also available for review in the Commission's Public Reference Room in Washington, DC. There is an eSubscription link on the Web site that enables subscribers to receive e-mail notification when a document is added to a subscribed docket(s). For assistance with any FERC Online service, please e-mail FERCOnlineSupport@ferc.gov or call (866) 208-3676 (toll free). For TTY, call (202) 502-8659. Dated: June 20, 2011. Kimberly D. Bose, Secretary. [FR Doc. 2011-15859 Filed 6-23-11; 8:45 am]

Multiterminal HVDC systems present challenges in the specification and design of suitable dc side filtering. This document examines the existing experience and addresses the particular technical problems posed by multiterminal systems. The filtering requirements of small taps are discussed, as is the potential use of active filters. Aspects of calculation and design are considered and recommendations made to guide the planners and designers of future multiterminal schemes.

Shortly after the beginning of the twentieth century, dc power transmission was replaced by ac in order to achieve efficient transmission of electric power over long distances with available conductors and at safe distribution voltages. However, dc power was not completely abandoned, and the advent of solid-state power electronic ac-to-dc conversion equipment has reinvigorated its application. High-voltage dc power is more desirable for long-range transmission than ac in many ways: dc uses two wires rath...

System planners have grown more interest in the prospect of converting ac transmission lines to dc as transfer constraints become more severe and they increasingly recognize dc as a means to improve ac system performance. Two factors have influenced the economic case for conversion. The first is development of a new (tripole) dc configuration that allows dc to make full use of all three ac phase positions without the need for earth return. The second is the realization that converting an ac line to dc ma...

The Electric Power Research Institute (EPRI) has developed a new energy-economy model of the United States under the PRISM 2.0 project called the U.S. Regional Economy, Greenhouse Gas, and Energy (US-REGEN) Model. The model combines a detailed dispatch and capacity expansion model of the United States electric sector with a high-level dynamic computable general equilibrium (CGE) model of the United States economy. ...

Washington DC Washington DC Energy Incentive Programs, Washington DC October 29, 2013 - 11:29am Addthis Updated August 2013 What public-purpose-funded energy efficiency programs are available in the District of Columbia? In 2008, the Council of the District of Columbia passed the Clean and Affordable Energy Act (CAEA), establishing the DC Sustainable Energy Utility (DC SEU), whose mission is to provide energy assistance to low-income residents and support energy efficiency and renewable energy programs. The DC SEU, funded by the Sustainable Energy Trust Fund (also created by the CAEA) and under contract to the District Department of the Environment (DDOE), helps District residents, businesses, and institutions save energy and money. The DC SEU provides comprehensive energy services to targeted, prioritized

In this thesis analysis and design of a wide input range DC-DC converter is proposed along with a robust power control scheme. The proposed converter and its control is designed to be compatible to a fuel cell power source, which exhibits 2:1 voltage variation as well as a slow transient response. The proposed approach consists of two stages: a primary three-level boost converter stage cascaded with a high frequency, isolated boost converter topology, which provides a higher voltage gain and isolation from the input source. The function of the first boost converter stage is to maintain a constant voltage at the input of the cascaded DC-DC converter to ensure optimal performance characteristics with high efficiency. At the output of the first boost converter a battery or ultracapacitor energy storage is connected to take care of the fuel cell slow transient response (200 watts/min). The robust features of the proposed control system ensure a constant output DC voltage for a variety of load fluctuations, thus limiting the power being delivered by the fuel cell during a load transient. Moreover, the proposed configuration simplifies the power control management and can interact with the fuel cell controller. The simulation results and the experimental results confirm the feasibility of the proposed system.

Single cell solid oxide regenerative fuel cells (SORFCs) have been demonstrated for over 1000 hours of operation at degradation rates as low as 0.5% per thousand hours for current densities as high as 300mA/cm{sup 2}. Efficiency levels (fuel cell power out vs. electrolysis power in) have been demonstrated in excess of 80% at 100mA/cm{sup 2}. All testing has been performed with metallic based interconnects and non-noble metal electrodes in order to limit fabrication costs for commercial considerations. The SORFC cell technology will be scaled up to a 1kW sized stack which will be demonstrated in Year 2 of the program. A self contained SORFC system requires efficient thermal management in order to maintain operating temperatures during exothermic and endothermic operational modes. The use of LiF as a phase change material (PCM) was selected as the optimum thermal storage medium by virtue of its superior thermal energy density by volume. Thermal storage experiments were performed using LiF and a simulated SORFC stack. The thermal storage concept was deemed to be technically viable for larger well insulated systems, although it would not enable a high efficiency thermally self-sufficient SORFC system at the 1 kW level.

A cycle has been conceived that combines compressor cooling, humidification, and regenerative air heating with the added enhancement of direct injection of water into the air flow. In this cycle it is proposed that a fine mist of water be injected into the compressor air stream and a spray or film of water into the regenerator air stream. Water injection into the compressor air flow realizes several benefits: it cools the air flow, reducing the power required for compression and increasing the potential for exhaust heat recovery; it adds mass to the air stream, increasing the power produced by expansion; and it reduces the amount of cooling bleed air required by increasing the specific heat and decreasing the temperature of the cooling air stream. The greatest benefit would be derived from spraying a fine mist of water directly into the existing air flow into or before the compressor so that cooling and compression would occur simultaneously. This may be accomplished by entraining the water droplets in the inlet air flow or by introducing the water in stages during compression. An alternative and less technically challenging approach is to extract the air stream to a saturation chamber and then reintroduce the air stream into the compressor. This approach is not as desirable because it would increase the equipment cost and add a significant pressure drop penalty. The second use of water in this cycle is in water-assisted regeneration.

A coal combustor/gasifier is disclosed which produces a low or medium combustion gas for further combustion in modified oil or gas fired furnaces or boilers. Two concentric shells define a combustion volume within the inner shell and a plenum between them through which combustion air flows to provide regenerative cooling of the inner shell for dry ash operation. A fuel flow and a combustion air flow having opposed swirls are mixed and burned in a mixing-combustion portion of the combustion volume and the ash laden combustion products flow with a residual swirl into an ash separation region. The ash is cooled below the fusion temperature and is moved to the wall by centrifugal force where it is entrained in the cool wall boundary layer. The boundary layer is stabilized against ash re-entrainment as it is moved to an ash removal annulus by a flow of air from the plenum through slots in the inner shell, and by suction on an ash removal skimmer slot.

The objective of this research is to develop a simple, yet accurate, lumped parameter mathematical model for an explosively driven magnetohydrodynamic generator that can predict the pulse power variables of voltage and current from startup through regenerative operation. The inputs to the model will be the plasma properties entering the generator as predicted by the explosive shock model of Reference [1]. The strategy used was to simplify electromagnetic and thermodynamic three dimensional effects into a zero dimensional model. The model will provide a convenient tool for researchers to optimize designs to be used in pulse power applications. The model is validated using experimental data of Reference [1]. An overview of the operation of the explosively driven generator is first presented. Then a simplified electrical circuit model that describes basic performance of the device is developed. Then a lumped parameter model that incorporates the coupled electromagnetic and thermodynamic effects that govern generator performance is described and developed. The model is based on fundamental physical principles and parameters that were either obtained directly from design data or estimated from experimental data. The model was used to obtain parameter sensitivities and predict beyond the limits observed in the experiments to the levels desired by the potential Department of Defense sponsors. The model identifies process limitations that provide direction for future research.

Thermally regenerative electrochemical systems (TRES) are closed systems that convert heat into electricity in an electrochemical heat engine that is Carnot cycle limited in efficiency. Past and present work on such systems is reviewed. Two broad classes of TRES are based on the types of energy inputs required for regeneration: thermal alone and coupled thermal and electrolytic. The thermal regeneration alone encompasses electrochemical systems (galvanic or fuel cells) in which one or more products are formed. The regeneration can be performed in single or multiple steps. The compounds include metal hydrides, halides, oxides, chalcogenides, and alloys or bimetallic systems. The coupled thermal and electrolytic regeneration encompasses electrochemical systems (galvanic or fuel cells) regenerated by electrolysis at a different temperature or different pressure. Examples include metal halides and water. Thermogalvanic or nonisothermal cells are included in this category. Also included are electrochemical engines in which the working electroactive fluid is isothermally expanded through an electrolyte. TRES cover temperature ranges from about 20/sup 0/C to 1000/sup 0/C. Engines with power outputs of 0.1 mW/cm/sup 2/ to 1 W/cm/sup 2/ have been demonstrated. Recommendations are made of areas of research in science and engineering that would have long-range benefit to a TRES program.

The pending OSHA standard revision proposed in 1990 to lower the asbestos Permissible Exposure Limit (PEL) and to mandate effective asbestos control measures (ACM) in brake and clutch assembly work may have a profound effect on industries involved in such operations. Health protection of workers will be improved and costs of improved control methods and training will increase. Considering these facts, this preliminary study was designed to assess the level of worker and management awareness of asbestos hazards associated with brake and clutch repair and to determine what ACM had been implemented by businesses in Knoxville and Knox County, Tennessee. The study, in a metropolitan area of approximately 336,000 people, revealed eight different categories of businesses conducting brake and clutch repair work with an estimated 363 potentially exposed employees. Results of the study suggest that managers and employees of the 80 businesses studied were in need of asbestos hazard awareness training and more adequate asbestos control measures.

The upgrade of the trackers at the sLHC experiments requires implementing new powering schemes that will provide an increased power density with reduced losses and material budget. A scheme based on buck and switched capacitors DC to DC converters has been proposed as an optimal solution. The buck converter is based on a power ASIC, connected to a custom made air core inductor. The arrangement of the parts and the board layout of the power module are designed to minimize the emissions of EMI in a compact volume, enabling its integration on the tracker modules and staves.

Washington DC's First Electric Vehicle Charging Station Washington DC's First Electric Vehicle Charging Station Washington DC's First Electric Vehicle Charging Station November 17, 2010 - 11:28am Addthis Street signage for Washington, DC's first electric vehicle charging station located on the northwest corner of the intersection of U and 14th streets. | Department of Energy Photo | Street signage for Washington, DC's first electric vehicle charging station located on the northwest corner of the intersection of U and 14th streets. | Department of Energy Photo | Shannon Brescher Shea Communications Manager, Clean Cities Program It's always exciting to attend a grand opening, especially when it represents a "first" for an entire region. Yesterday, the U.S. Department of Energy and the city of Washington, DC joined together to

High Altitude Long Endurance (HALE) unmanned missions appear to be feasible using a lightweight, high efficiency, span-loaded, Solar Powered Aircraft (SPA) which includes a Regenerative Fuel Cell (RFC) system and novel tankage for energy storage. An existing flightworthy electric powered flying wing design was modified to incorporate present and near-term technologies in energy storage, power electronics, aerodynamics, and guidance and control in order to design philosophy was to work with vendors to identify affordable near-term technological opportunities that could be applied to existing designs in order to reduce weight, increase reliability, and maintain adequate efficiency of components for delivery within 18 months. The energy storage subsystem for a HALE SPA is a key driver for the entire vehicle because it can represent up to half of the vehicle weight and most missions of interest require the specific energy to be considerably higher than 200 W-hr/kg for many cycles. This stringent specific energy requirement precludes the use of rechargeable batteries or flywheels and suggests examination of various RFC designs. An RFC system using lightweight tankage, a single fuel cell (FC) stack, and a single electrolyzer (EC) stack separated by the length of a spar segment (up to 39 ft), has specific energy of {approximately}300 W-hr/kg with 45% efficiency, which is adequate for HALE SPA requirements. However, this design has complexity and weight penalties associated with thermal management, electrical wiring, plumbing, and structural weight. A more elegant solution is to use unitized RFC stacks (reversible stacks that act as both FCs and ECs) because these systems have superior specific energy, scale to smaller systems more favorably, and have intrinsically simpler thermal management.

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Instrument-limited suppression of out-of-band Amplified Spontaneous Emission (ASE) is demonstrated in a Nd:YLF Diode-Pumped Regenerative Amplifier (DPRA) using a Volume Bragg Grating (VBG) as a spectrally selective reflective element. A VBG with 99.4% diffraction efficiency and 230-pm-FWHM reflection bandwidth produced a 43-pm-FWHM output spectral width in an unseeded DPRA compared to 150-pm FWHM in the same DPRA with no VBG. Instrument-limited ASE suppression is even observed when the DPRA seed pulse energy approaches the ASE background.

The authors designed, implemented and tested cryogenic RF filters with zero DC resistance, based on wires with a superconducting core inside a resistive sheath. The superconducting core allows low frequency currents to pass with negligible dissipation. Signals above the cutoff frequency are dissipated in the resistive part due to their small skin depth. The filters consist of twisted wire pairs shielded with copper tape. Above approximately 1 GHz, the attenuation is exponential in {radical}{omega}, as typical for skin depth based RF filters. By using additional capacitors of 10 nF per line, an attenuation of at least 45 dB above 10 MHz can be obtained. Thus, one single filter stage kept at mixing chamber temperature in a dilution refrigerator is sufficient to attenuate room temperature black body radiation to levels corresponding to 10 mK above about 10 MHz.

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Is the Energy Race our new Is the Energy Race our new "Sputnik" Moment? National Press Club Washington, D.C. 29 November, 2010 1 October 4, 1957, the Soviet Union placed a 184 pound satellite into orbit. "The Soviet Union now has - in the combined category of scientists and engineers - a greater number than the United States. And it is producing graduates in these fields at a much faster rate ... This trend is disturbing. Indeed, according to my scientific advisers, this is for the American people the most critical problem of all. My scientific advisers place this problem above all other immediate tasks of producing missiles, of developing new techniques in the Armed Services. We need scientists in the ten years ahead..." On November 13, 1957, President Eisenhower

As part of the Enhance Surveillance mission, it is the goal to provide suitable lifetime assessment of stockpile materials. This report is an accumulation of historical publication on the DC745U material and their findings. It is the intention that the B61 LEP program uses this collection of data to further develop their understanding and potential areas of study. DC745U is a commercially available silicone elastomer consisting of dimethyl, methyl-phenyl, and methyl-vinyl siloxane repeat units. Originally, this material was manufactured by Dow Corning as Silastic{reg_sign} DC745U at their manufacturing facility in Kendallville, IN. Recently, Dow Corning shifted this material to the Xiameter{reg_sign} brand product line. Currently, DC745U is available through Xiameter{reg_sign} or Dow Corning's distributor R. D. Abbott Company. DC745U is cured using 0.5 wt% vinyl-specific peroxide curing agent known as Luperox 101 or Varox DBPH-50. This silicone elastomer is used in numerous parts, including two major components (outer pressure pads and aft cap support) in the W80 and as pressure pads on the B61. DC745U is a proprietary formulation, thus Dow Corning provides limited information on its composition and properties. Based on past experience with Dow Corning, DC745U is at risk of formulation changes without notification to the costumer. A formulation change for DC745U may have a significant impact because the network structure is a key variable in determining material properties. The purpose of this report is to provide an overview of historical DC745U studies and identify gaps that need to be addressed in future work. Some of the previous studies include the following: 1. Spectroscopic characterization of raw gum stock. 2. Spectroscopic, thermal, and mechanical studies on cured DC745U. 3. Nuclear Magnetic Resonance (NMR) and solvent swelling studies on DC745U with different crosslink densities. 4. NMR, solvent swelling, thermal, and mechanical studies on thermally aged DC745U. 5. NMR, solvent swelling, thermal, and mechanical studies on radiolytically aged DC745U. Each area is reviewed and further work is suggested to improve our understanding of DC745U for systems engineering, surveillance, aging assessments, and lifetime assessment.

There is vital need for a compact, lightweight, and efficient energy-storage system that is both affordable and has an acceptable cycle life for the large-scale production of electric vehicles (EVs) and hybrid electric vehicles (HEVs). Most of the current research employs a battery-storage unit (BU) combined with a fuel cell (FC) stack in order to achieve the operating voltage-current point of maximum efficiency for the FC system. A system block diagram is shown in Fig.1.1. In such a conventional arrangement, the battery is sized to deliver the difference between the energy required by the traction drive and the energy supplied by the FC system. Energy requirements can increase depending on the drive cycle over which the vehicle is expected to operate. Peak-power transients result in an increase of losses and elevated temperatures which result in a decrease in the lifetime of the battery. This research will propose a novel two-input direct current (dc) dc to dc converter to interface an additional energy-storage element, an ultracapacitor (UC), which is shown in Fig.1.2. It will assist the battery during transients to reduce the peak-power requirements of the battery.

An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.

An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.

This study covers the use of dc generators for meeting the Experimental Power Reactor Ohmic Heating Energy Storage Requirements. The dc generators satisfy these requirements which are the same as defined in WFPS-TME-038 which covered the use of ac generators and homopolar generators. The costs of the latter two systems have been revised to eliminate first-of-a-kind factors. The cost figures for dc generators indicate a need to develop larger machines in order to take advantage of the economy-of-scale that the large ac machines have. Each of the systems has its own favorable salient features on which to base a system selection.

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Plug-in hybrid electric vehicles (PHEVs) will play a vital role in future sustainable transportation systems due to their potential in terms of energy security, decreased environmental impact, improved fuel economy, and better performance. Moreover, new regulations have been established to improve the collective gas mileage, cut greenhouse gas emissions, and reduce dependence on foreign oil. This paper primarily focuses on two major thrust areas of PHEVs. First, it introduces a grid-friendly bidirectional alternating current/direct current ac/dcdc/ac rectifier/inverter for facilitating vehicle-to-grid (V2G) integration of PHEVs. Second, it presents an integrated bidirectional noninverted buck boost converter that interfaces the energy storage device of the PHEV to the dc link in both grid-connected and driving modes. The proposed bidirectional converter has minimal grid-level disruptions in terms of power factor and total harmonic distortion, with less switching noise. The integrated bidirectional dc/dc converter assists the grid interface converter to track the charge/discharge power of the PHEV battery. In addition, while driving, the dc/dc converter provides a regulated dc link voltage to the motor drive and captures the braking energy during regenerativebraking.

A low noise radiofrequency amplifer, using a dc SQUID (superconducting quantum interference device) as the input amplifying element. The dc SQUID and an input coil are maintained at superconductivity temperatures in a superconducting shield, with the input coil inductively coupled to the superconducting ring of the dc SQUID. A radiofrequency signal from outside the shield is applied to the input coil, and an amplified radiofrequency signal is developed across the dc SQUID ring and transmitted to exteriorly of the shield. A power gain of 19.5 +- 0.5 dB has been achieved with a noise temperature of 1.0 +- 0.4 K at a frequency of 100 MHz.

A low noise radiofrequency amplifier (10), using a dc SQUID (superconducting quantum interference device) as the input amplifying element. The dc SQUID (11) and an input coil (12) are maintained at superconductivity temperatures in a superconducting shield (13), with the input coil (12) inductively coupled to the superconducting ring (17) of the dc SQUID (11). A radiofrequency signal from outside the shield (13) is applied to the input coil (12), and an amplified radiofrequency signal is developed across the dc SQUID ring (17) and transmitted to exteriorly of the shield (13). A power gain of 19.5.+-.0.5 dB has been achieved with a noise temperature of 1.0.+-.0.4 K. at a frequency of 100 MHz.

Titanium nitride is of interest for IC fabrication because of its excellent performance as a metallic diffusion barrier. TiN films have been deposited in a batch sputtering system equipped with dc magnetron cathodes

Washington DC Reliability Requirements and the Need to Operate Washington DC Reliability Requirements and the Need to Operate Mirant's Potomac River Generation Station to Support Local Area Reliability (Oak Ridge National Laboratory 2005) Washington DC Reliability Requirements and the Need to Operate Mirant's Potomac River Generation Station to Support Local Area Reliability (Oak Ridge National Laboratory 2005) Pursuant to Docket No. EO-05-01: Oak Ridge National Laboratory provided an analysis of the Mirant Potomac River Generation Station in 2005 and discussed the reliability requirements of the local area and the potential impacts on reliability of changing operation of the Potomac River Generating Station in this paper. Washington DC Reliability Requirements and the Need to Operate Mirant's Potomac River Generation Station to Support Local Area Reliability.pdf

This manuscript focuses on a novel actively controlled hybrid magnetic battery/ultracapacitor based energy storage system (ESS) for vehicular propulsion systems. A stand-alone battery system might not be sufficient to satisfy peak power demand and transient load variations in hybrid and plug-in hybrid electric vehicles (HEV, PHEV). Active battery/ultracapacitor hybrid ESS provides a better solution in terms of efficient power management and control flexibility. Moreover, the voltage of the battery pack can be selected to be different than that of the ultracapacitor, which will result in flexibility of design as well as cost and size reduction of the battery pack. In addition, the ultracapacitor bank can supply or recapture a large burst of power and it can be used with high C-rates. Hence, the battery is not subjected to supply peak and sharp power variations, and the stress on the battery will be reduced and the battery lifetime would be increased. Utilizing ultracapacitor results in effective capturing of the braking energy, especially in sudden braking conditions.

Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage [14 V, 42 V, and high voltage (HV)] nets. These will be necessary to accommodate existing 14-V loads as well as efficiently handle new heavy loads at the 42-V net and a traction drive on the HV bus. A low-cost DC-DC converter was proposed for connecting the three voltage nets. It minimizes the number of switches and their associated gate driver components by using two half-bridges and a high-frequency transformer. Another salient feature is that the half bridge on the 42-V bus is also utilized to provide the 14-V bus by operating at duty ratios around an atypical value of 1/3. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft switching. The use of half bridges makes the topology well suited for interleaved multiphase modular configurations as a means to increase the power level because the capacitor legs can be shared. This paper presents simulation and experimental results on an interleaved two-phase arrangement rated at 4.5 kW. Also discussed are the benefits of operating with an atypical duty ratio on the transformer and a preferred multiphase configuration to minimize capacitor ripple currents.

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Adjustable speed drive (ASD) ride-through issues have caused increased concerns due to drive susceptibility to power disturbances and the costly results of process disruptions. Losses incurred due to DC drive trips can be avoided for critical production processes by employing ride-through alternatives. The purpose of this study is to determine the DC drive ride-through requirements of industrial customers and match those ride-through needs with possible solutions.

This report presents results of an extensive laboratory assessment of the impact of DC load currents (including half-wave rectified loads) on the metrological accuracy of residential solid state electricity meters. Sampled surveys were conducted to determine whether products producing DC currents are prevalent in residential premises. In addition, regulations and codes were studied to determine whether such products could naturally appear in the marketplace going forward. Two each of six brands of socket...

This report presents an assessment of market, energy impact, and utility of the PetroTex Hydrocarbons, LLC., ReGen process for re-refining used lubricating oil to produce Group I, II, and III base oils, diesel fuel, and asphalt. PetroTex Hydrocarbons, LLC., has performed extensive pilot scale evaluations, computer simulations, and market studies of this process and is presently evaluating construction of a 23 million gallon per year industrial-scale plant. PetroTex has obtained a 30 acre site in the Texas Industries RailPark in Midlothian Texas. The environmental and civil engineering assessments of the site are completed, and the company has been granted a special use permit from the City of Midlothian and air emissions permits for the Texas Commission on Environmental Quality.

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Although battery technology is relatively mature, power sources continue to impose serious limitations for small, portable, mobile, or remote applications. A potentially attractive alternative to batteries is chemical fuel-to-electric conversion. Chemical fuels have volumetric energy densities 4 to 10 times those of batteries. However, realizing this advantage requires efficient chemical fuel-to-electric conversion. Direct electrochemical conversion would be the ideal, but, for most fuels, is generally not within the state-of-the-science. Next best, chemical-to-thermal-to-electric conversion can be attractive if efficiencies can be kept high. This small investigative project was an exploration into the feasibility of a novel hybrid (i.e., thermal-electrochemical) micropower converter of high theoretical performance whose demonstration was thought to be within near-term reach. The system is comprised of a hydrogen concentration electrochemical cell with physically identical hydrogen electrodes as anode and cathode, with each electrode connected to physically identical hydride beds each containing the same low-enthalpy-of-formation metal hydride. In operation, electrical power is generated by a hydrogen concentration differential across the electrochemical cell. This differential is established via coordinated heating and passive cooling of the corresponding hydride source and sink. Heating is provided by the exothermic combustion (i.e., either flame combustion or catalytic combustion) of a chemical fuel. Upon hydride source depletion, the role of source and sink are reversed, heating and cooling reversed, electrodes commutatively reversed, cell operation reversed, while power delivery continues unchanged. This 'regenerative flip' of source and sink hydride beds can be cycled continuously until all available heating fuel is consumed. Electricity is efficiently generated electrochemically, but hydrogen is not consumed, rather the hydrogen is regeneratively cycled as an electrochemical 'working fluid'.

The field test project described in this report was conducted to evaluate the energy and environmental performance of 100% oxygen enriched combustion (100% OEC) in regenerative glass melters. Additional objectives were to determine other impacts of 100% OEC on melter operation and glass quality, and to verify on a commercial scale that an on-site Pressure Swing Adsorption oxygen plant can reliably supply oxygen for glass melting with low electrical power consumption. The tests constituted Phase 2 of a cooperative project between the United States Department of Energy, and Praxair, Inc. Phase 1 of the project involved market and technical feasibility assessments of oxygen enriched combustion for a range of high temperature industrial heating applications. An assessment of oxygen supply options for these applications was also performed during Phase 1, which included performance evaluation of a pilot scale 1 ton per day PSA oxygen plant. Two regenerative container glass melters were converted to 100% OEC operation and served as host sites for Phase 2. A 75 ton per day end-fired melter at Carr-Lowrey Glass Company in Baltimore, Maryland, was temporarily converted to 100% OEC in mid- 1990. A 350 tpd cross-fired melter at Gallo Glass Company in Modesto, California was rebuilt for permanent commercial operation with 100% OEC in mid-1991. Initially, both of these melters were supplied with oxygen from liquid storage. Subsequently, in late 1992, a Pressure Swing Adsorption oxygen plant was installed at Gallo to supply oxygen for 100% OEC glass melting. The particular PSA plant design used at Gallo achieves maximum efficiency by cycling the adsorbent beds between pressurized and evacuated states, and is therefore referred to as a Vacuum/Pressure Swing Adsorption (VPSA) plant.

Modulation of power transmitted over a proposed multiterminal dc system to provide effective stability enhancement of a large ac system in the Southwestern U.S. is demonstrated in this paper. This proposed multiterminal dc system connecting the Phoenix, Mead and Los Angeles areas could be in parallel with an Extra High-Voltage (EHV) ac transmission network which could be operating at heavy loading conditions. Studies indicated that the utilization of large power and reactive power modulation on the dc system can provide transient stability enhancements and ac system damping. The resultant system damping can be significantly improved when compared to the performance of the ac system prior to the addition of the dc system. The application of modulation permits the release of converter station vars to support the ac system voltage and thus reduces the required capability of voltage support devices.

This chapter describes an approach to the formalization of existing criteria used in computer systems software testing and proposes a Reinforced Condition/Decision Coverage (RC/DC) criterion. This criterion has been developed from the well-known Modified ...

f9-dc0d-45ef-9789-a7781dc1934b f9-dc0d-45ef-9789-a7781dc1934b No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: El Paso Electric Co (New Mexico) Effective date: 2010/01/01 End date if known: Rate name: LGS (Large General Service Secondary) Sector: Commercial Description: This rate is available to all Customers for lighting,power, and heating service. All service will be taken at one point of delivery designated by the Company and at one of the Company's standard types of service. Service under this rate shall be limited to Customers whose expected monthly demand will exceed 800 kilowatts (kW).

A highly efficient DC to DC converter has been developed for low-voltage high-current solid oxide fuel cells. The newly developed 'V6' converter resembles what has been done in internal combustion engine that split into multiple cylinders to increase the output capacity without having to increase individual cell size and to smooth out the torque with interleaving operation. The development was started with topology overview to ensure that all the DC to DC converter circuits were included in the study. Efficiency models for different circuit topologies were established, and computer simulations were performed to determine the best candidate converter circuit. Through design optimization including topology selection, device selection, magnetic component design, thermal design, and digital controller design, a bench prototype rated 5-kW, with 20 to 50V input and 200/400V output was fabricated and tested. Efficiency goal of 97% was proven achievable through hardware experiment. This DC to DC converter was then modified in the later stage to converter 35 to 63 V input and 13.8 V output for automotive charging applications. The complete prototype was tested at Delphi with their solid oxide fuel cell test stand to verify the performance of the modified DC to DC converter. The output was tested up to 3-kW level, and the efficiency exceeded 97.5%. Multiple-phase interleaving operation design was proved to be reliable and ripple free at the output, which is desirable for the battery charging. Overall this is a very successful collaboration project between the SECA Core Technology Team and Industrial Team.

The measurement of insulation resistance between DC power supply and ground is important in a DC operating power supply system. We proved a new model for measuring insulating resistance between ground and DC system. A lots of actual application shows ... Keywords: Insulation resistance, DC power system, Insulation monitor, Leakage current

Q&A: Kristen Psaki of WeatherizeDC Q&A: Kristen Psaki of WeatherizeDC Q&A: Kristen Psaki of WeatherizeDC April 15, 2010 - 3:45pm Addthis Roughly 20 percent of carbon emissions come from inefficient homes. The DC Project says it has found a way to mitigate emissions and create jobs, a winning combination. WeatherizeDC is the non-profit's effort to use a community engagement model to help DC residents find green jobs and live a more energy efficient lifestyle. Energy Empowers recently spoke with DC Project co-founder and creative director Kristen Psaki about WeatherizeDC's approach to climate change. WeatherizeDC is a nonprofit community engagement program. What's the background of it, the story of how and why it was founded? The DC Project was founded over a year ago in January 2009.

Q&A: Kristen Psaki of WeatherizeDC Q&A: Kristen Psaki of WeatherizeDC Q&A: Kristen Psaki of WeatherizeDC April 15, 2010 - 3:45pm Addthis Roughly 20 percent of carbon emissions come from inefficient homes. The DC Project says it has found a way to mitigate emissions and create jobs, a winning combination. WeatherizeDC is the non-profit's effort to use a community engagement model to help DC residents find green jobs and live a more energy efficient lifestyle. Energy Empowers recently spoke with DC Project co-founder and creative director Kristen Psaki about WeatherizeDC's approach to climate change. WeatherizeDC is a nonprofit community engagement program. What's the background of it, the story of how and why it was founded? The DC Project was founded over a year ago in January 2009.

In this paper, a comparative investigation of different random modulation schemes against the normal pulsewidth modulation (PWM) for the DC motor drive with step-down chopper (buck) and half-bridge configuration is presented. For this purpose, an experimental setup with DSP2 board has been developed. The board consists of the signal processor TMS320C32 which is suitable for verifying the different modulations strategies. The effectiveness of randomization on spreading the dominating frequencies that normally exist in constantfrequency PWM schemes is evaluated by the power spectral density (PSD) estimations in the low-frequency range. Finally, one universal demo board with two power converters configuration (driven by the micro controller PICF16F876) has been used in EMI measurements to comply with the CISPR 25 (or EN 55025) regulations. 1

Frequency-dependent effects in railway traction power systems arise from the impedance of substation and locomotive line filters and the traction line. Harmonic noise from traction drives and substations can excite resonances and produce overcurrent or overvoltage conditions at critical points in the network. In this paper, the harmonic feeding impedances of a 3 kV DC traction system seen from the rectifier substation, locomotive drive converter and pantograph terminals are presented. Several substation and locomotive filters are considered with a frequency-dependent traction line. Resonances attributed to the substation filter, locomotive filter and traction line are separate and distinct, the line introducing poles and zeros in the audio frequency (AF) range which vary in frequency and magnitude with locomotive position.

In recent years, there has been lots of emphasis put on the development of renewable energy. While considerable improvement on renewable energy has been made, there are some inherent limitations for these renewable energies. For example, for solar and wind power, there is an intermittent nature. For the fuel cell, the dynamics of electro-chemical reaction is quite slow compared to the electric load. This will not be acceptable for modern electric application, which requires constant voltage of constant frequency. This work proposed and evaluated a new power circuit that can deal with the problem of the intermittent nature and slow response of the renewable energy. The proposed circuit integrates different renewable energy sources as well as energy storage. By integrating renewable energy sources with statistical tendency to compensate each other, the effect of the intermittent nature can be greatly reduced. This integration will increase the reliability and utilization of the overall system. Moreover, the integration of energy storage solves the problem of the slow response of renewable energy. It can provide the extra energy required by load or absorb the excessive energy provided by the energy sources, greatly improving the dynamics of overall system. To better understand the proposed circuit, "Dual Active Bridge" and "Triple Active Bridge" were reviewed first. The operation principles and the modeling were presented. Analysis and design of the overall system were discussed. Controller design and stability issues were investigated. Furthermore, the function of the central controller was explained. In the end, different simulations were made and discussed. Results from the simulations showed that the proposed multi-port DC-DC power converter had satisfactory performance under different scenarios encountered in practical renewable energy application. The proposed circuit is an effective solution to the problem due to the intermittent nature and slow response of the renewable energy.

We presently enjoy a predominantly ac electrical distribution system, the engineering basis for which was designed over 100 years ago. While ac distribution systems have served us well, we should periodically pause to assess what opportunities we have accepted or been denied by the overwhelming predominance of ac electrical power distribution systems. What opportunities could be obtained by engineering dc distribution into at least portions of our present system? What advantages of the present ac distribution system should be recognized and protected? This paper will focus on distribution within premise and low-voltage distribution systems. Specifically, we will address the conversion efficiency costs of adopting various premise ac and dc distribution system topologies. According to a simple predictive model formulated in this paper, premise residential dc distribution will incur unfavorable total conversion efficiency compared with existing ac premise distribution. However, if a residence is supplied by a fuel cell or another dc generator, the total conversion efficiency within a residential dc distribution system could be similar to, or even better than, that for ac distribution.

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3 Aerial view of Washington D.C. 3 Aerial view of Washington D.C. News From the D.C. Office Efficient Office Equipment: Update and a Look Ahead An extended version of this article is available here. We are now well aware of the large amount of energy consumed by "plug-in loads" such as personal computers (PCs) and other office electronics. Office equipment is often cited as the fastest-growing end-use of electricity in the fastest-growing sector of demand (commercial buildings). According to Dataquest figures, world growth of PCs will average 14 to 15 percent per year through 1999. Only ten years ago, office equipment was not even part of the "map" of non-residential energy end-uses. There were virtually no data on office equipment energy use, nor an awareness of the

Completes Cool Roof Installation on DC Completes Cool Roof Installation on DC Headquarters Building to Save Money by Saving Energy Energy Department Completes Cool Roof Installation on DC Headquarters Building to Save Money by Saving Energy December 14, 2010 - 12:00am Addthis Washington - Secretary Steven Chu today announced the completion of a new cool roof installation on the Department of Energy's Headquarters West Building. There was no incremental cost to adding the cool roof as part of the roof replacement project and it will save taxpayers $2,000 every year in building energy costs. Cool roofs use lighter-colored roofing surfaces or special coatings to reflect more of the sun's heat, helping improve building efficiency, reduce cooling costs and offset carbon emissions. The cool roof and increased insulation at the facility were

Argonne's Through-the-Road Hybrid goes to Washington, D.C., Auto Show Argonne's Through-the-Road Hybrid goes to Washington, D.C., Auto Show Argonne's Through the Road Vehicle Argonne's Through-the-Road Hybrid Vehicle Argonne's Through-the-Road hybrid vehicle (TTR) will be on display at the Washington Auto Show at Walter E. Washington Convention Center, February 4-8, 2009, in Washington, D.C. The TTR will be in the combined U.S. Department of Energy, Environmental Protection Agency, and Department of Transportation exhibit booth that features advanced vehicle technologies that are safe, clean, and efficient. Due to power-split limitations, no plug-in hybrid electric vehicle (PHEV) exists that can complete an Urban Dynamometer Driving Schedule (UDDS) cycle without starting the engine. Argonne created the TTR, an in-house PHEV development platform with an open

Capitol DC Capitol DC Below you will find Solar Decathlon news from the Team Capitol DC archive, sorted by date. Hangout With Solar Decathlon 2013 Teams on Sept. 18! Wednesday, September 11, 2013 By Rebecca Matulka Editor's Note: This entry has been cross-posted from DOE's Energy Blog. Photo of a Solar Decathlon house at night. Superimposed is the following text: "Solar Decathlon 2013: The Path to a Brighter Future. Energy.gov/live. Wednesday, Sept. 18, at p.m. ET. #askSD." Mark your calendars for a Google+ Hangout on Solar Decathlon 2013: The Path to a Brighter Future on Wednesday, Sept. 18, at 2 p.m. ET. For more than 10 years, the U.S. Department of Energy Solar Decathlon has been preparing the next wave of energy leaders-providing hands-on experience in designing and building energy-efficient, solar-powered

The development and fabrication of dc SQUIDs (Superconducting QUantum Interference Devices) with Nb/Al{sub 2}O{sub 3}/Nb Josephson junctions is described. A theory of the dc SQUID as a radio-frequency amplifier is presented, with an optimization strategy that accounts for the loading and noise contributions of the postamplifier and maximizes the signal-to-noise ratio of the total system. The high sensitivity of the dc SQUID is extended to high field NMR. A dc SQUID is used as a tuned radio-frequency amplifier to detect pulsed nuclear magnetic resonance at 32 MHz from a metal film in a 3.5 Tesla static field. A total system noise temperature of 11 K has been achieved, at a bath temperature of 4.2 K. The minimum number of nuclear Bohr magnetons observable from a free precession signal after a single pulse is about 2 {times} 10{sup 17} in a bandwidth of 25 kHz. In a separate experiment, a dc SQUID is used as a rf amplifier in a NQR experiment to observe a new resonance response mechanism. The net electric polarization of a NaClO{sub 3} crystal due to the precessing electric quadrupole moments of the Cl nuclei is detected at 30 MHz. The sensitivity of NMR and NQR spectrometers using dc SQUID amplifiers is compared to the sensitivity of spectrometers using conventional rf amplifiers. A SQUID-based spectrometer has a voltage sensitivity which is comparable to the best achieved by a FET-based spectrometer, at these temperatures and operating frequencies.

A model is developed and numerical calculations are performed for the regenerative amplification of seed picosecond 10-{mu}m radiation pulses in a high-pressure optically pumped CO{sub 2} laser. It is established that by varying the cavity parameters, the conditions of efficient regenerative amplification may be optimised for the case of a relatively short-duration (50 ns) solid-state Cr:Er:YSGG laser and 'long-duration' (250 ns) electrodischarge chemical HF laser. It is shown that the schemes of a CO{sub 2} amplifier with optical pumping presented allow obtaining the pulses with the duration of 3ps, output energy of 1-5 mJ, and peak power of {approx}1 GW at the pump energy of 150-200 mJ. (lasers and amplifiers)

Under the PRISM 2.0 Project, the Electric Power Research Institute (EPRI) developed the U.S. Regional Economy, Greenhouse Gas, and Energy (US-REGEN) model that can assess the impact of various climate, energy, and environmental policies on the electric power sector, the energy system, and the overall U.S. economy. This model represents energy efficiency potential through elasticities of substitution between energy and capital. EPRI has contracted with M. K. Jaccard and Associates Inc. to determine ...

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules.

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules. 5 Figs.

The purpose of introducing active dc filters is to meet the more and more stringent requirement from power utilities on limiting telephone interference caused by harmonic currents from HVdc transmission lines, without unnecessarily increasing the cost of HVdc stations. An active dc filter installed in the Konti-Skan HVdc link is described. The active dc filter is connected at the bottom of an existing passive dc filter at the Lindome station. The active dc filter includes optic harmonic current measuring unit, control system, protection and supervision system, PWM power amplifier, high-frequency transformer, surge arrester, and coupling apparatuses. The active dc filter has small physical size and occupies small ground area. The performance of the active dc filter for eliminating the disturbing harmonics is excellent. To achieve comparable results by passive filters would require something like ten times more high voltage equipment.

A detailed description of the design, operation, and maintenance of the Integrated Test Vehicle (ITV) including instruments and controls, economy, safety and security, troubleshooting, and specifications is given. The ITV employs a dc traction motor and 18 lead-acid batteries which provide a nominal voltage of 108 Vdc. A microcomputer controls many vehicle electrical functions. The ITV is a four-passenger subcompact weighing 3320 lb curb weight with the capacity of carrying a 600 lb payload. The driving range is 75 miles on urban cycle, and the vehicle is equipped with a regenerativebraking system. (WHK)

With the ever-growing developments of sustainable energy sources such as fuel
cells, photovoltaics, and other distributed generation, the need for a reliable power
conversion system that interfaces these sources is in great demand. In order to provide
the highest degree of flexibility in a truly distributed network, it is desired to not only
interface multiple sources, but to also interface multiple loads. Modern multi-port
converters use high frequency transformers to deliver the different power levels, which
add to the size and complexity of the system. The different topological variations of the
proposed multi-port dc-dc converter have the potential to solve these problems.
This thesis proposes a unique dc-dc current source converter for multi-port power
conversion. The presented work will explain the proposed multi-port dc-dc converter's
operating characteristics, control algorithms, design and a proof of application. The
converter will be evaluated to determine its functionality and applicability. Also, it will
be shown that our converter has advantages over modern multi-port converters in its ease
of scalability from kW to MW, low cost, high power density and adaption to countless combinations of multiple sources. Finally we will present modeling and simulation of
the proposed converter using the PSIM software.
This research will show that this new converter topology is unstable without
feedback control. If the operating point is moved, one of the source ports of the multiport
converter becomes unstable and dies off supplying very little or no power to the
load while the remaining source port supplies all of the power the load demands. In
order to prevent this and add stability to the converter a simple yet unique control
method was implemented. This control method allowed for the load power demanded to
be shared between the two sources as well as regulate the load voltage about its desired
value.

Femtosecond lasers are a powerful tool for a wealth of applications in physics, chemistry and biology. In most cases, however, their use is fundamentally restricted to a rather narrow spectral range. This thesis deals with the construction and characterization of a femtosecond light source for spectroscopic applications which overcomes that restriction. It is demonstrated how the output of a continuously pumped Ti:sapphire femtosecond oscillator is amplified to the {mu}J level, while the pulse duration remains below 100fs. A combination of continuous pumping, acousto-optic switching and Ti:Al{sub 2}O{sub 3} as a gain medium allows amplification at high repetition rates. By focusing the high energy pulses into a sapphire crystal, a broad-band continuum can be generated, extended in wavelengths over several hundred nanometers. To accomplish amplification of three orders of magnitude while maintaining the pulse length, a regenerative multipass amplifier system was built. The thesis describes theoretical design, realization and characterization of the system. Theoretical calculations and preliminary measurements were carried out and allow a critical evaluation of the final performance.

Femtosecond lasers are a powerful tool for a wealth of applications in physics, chemistry and biology. In most cases, however, their use is fundamentally restricted to a rather narrow spectral range. This thesis deals with the construction and characterization of a femtosecond light source for spectroscopic applications which overcomes that restriction. It is demonstrated how the output of a continuously pumped Ti:sapphire femtosecond oscillator is amplified to the {mu}J level,while the pulse duration remains below 100 fs. A combination of continuous pumping, acousto-optic switching and Ti:Al{sub 2}O{sub 3} as a gain medium allows amplification at high repetition rates. By focusing the high energy pulses into a sapphire crystal, a broad-band continuum can be generated, extended in wavelengths over several hundred nanometers. To accomplish amplification of three orders of magnitude while maintaining the pulse length, a regenerative multipass amplifier system was built. The thesis describes theoretical design, realization and characterization of the system. Theoretical calculations and preliminary measurements were carried out and allow a critical evaluation of the final performance.

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An improved electrostatic coalescence system is provided in which independent AC and DC hydrophilic electrodes are employed to provide more complete dehydration of an oil emulsion. The AC field is produced between an AC electrode array and the water-oil interface wherein the AC electrode array is positioned parallel to the interface which acts as a grounded electrode. The emulsion is introduced into the AC field in an evenly distributed manner at the interface. The AC field promotes drop-drop and drop-interface coalescence of the water phase in the entering emulsion. The continuous oil phase passes upward through the perforated AC electrode array and enters a strong DC field produced between closely spaced DC electrodes in which small dispersed droplets of water entrained in the continuous phase are removed primarily by collection at hydrophilic DC electrodes. Large droplets of water collected by the electrodes migrate downward through the AC electrode array to the interface. All phase separation mechanisms are utilized to accomplish more complete phase separation.

In this project, we have developed the use of thin-film magnetic materials to improve in energy efficiency of digital computing applications by enabling integrated dc-dc power conversion and management with on-chip power inductors. Integrated voltage regulators also enables fine-grained power management, by providing dynamic scaling of the supply voltage in concert with the clock frequency of synchronous logic to throttle power consumption at periods of low computational demand. The voltage converter generates lower output voltages during periods of low computational performance requirements and higher output voltages during periods of high computational performance requirements. Implementation of integrated power conversion requires high-capacity energy storage devices, which are generally not available in traditional semiconductor processes. We achieve this with integration of thin-film magnetic materials into a conventional complementary metal-oxide-semiconductor (CMOS) process for high-quality on-chip power inductors. This project includes a body of work conducted to develop integrated switch-mode voltage regulators with thin-film magnetic power inductors. Soft-magnetic materials and inductor topologies are selected and optimized, with intent to maximize efficiency and current density of the integrated regulators. A custom integrated circuit (IC) is designed and fabricated in 45-nm CMOS silicon-on-insulator (SOI) to provide the control system and power-train necessary to drive the power inductors, in addition to providing a digital load for the converter. A silicon interposer is designed and fabricated in collaboration with IBM Research to integrate custom power inductors by chip stacking with the 45-nm CMOS integrated circuit, enabling power conversion with current density greater than 10A/mm2. The concepts and designs developed from this work enable significant improvements in performance-per-watt of future microprocessors in servers, desktops, and mobile devices. These new approaches to scaled voltage regulation for computing devices also promise significant impact on electricity consumption in the United States and abroad by improving the efficiency of all computational platforms. In 2006, servers and datacenters in the United States consumed an estimated 61 billion kWh or about 1.5% of the nation's total energy consumption. Federal Government servers and data centers alone accounted for about 10 billion kWh, for a total annual energy cost of about $450 million. Based upon market growth and efficiency trends, estimates place current server and datacenter power consumption at nearly 85 billion kWh in the US and at almost 280 billion kWh worldwide. Similar estimates place national desktop, mobile and portable computing at 80 billion kWh combined. While national electricity utilization for computation amounts to only 4% of current usage, it is growing at a rate of about 10% a year with volume servers representing one of the largest growth segments due to the increasing utilization of cloud-based services. The percentage of power that is consumed by the processor in a server varies but can be as much as 30% of the total power utilization, with an additional 50% associated with heat removal. The approaches considered here should allow energy efficiency gains as high as 30% in processors for all computing platforms, from high-end servers to smart phones, resulting in a direct annual energy savings of almost 15 billion kWh nationally, and 50 billion kWh globally. The work developed here is being commercialized by the start-up venture, Ferric Semiconductor, which has already secured two Phase I SBIR grants to bring these technologies to the marketplace.

A new type of powerline communication is developed to reduce cable requirements for robotic, electromechanical, and vehicular systems. A DC power bus line connecting a DC power supply to motor drives and sensor units is ...

The power restoration timeline suggested by the DC power flow and the Angle Constrained DC power flow is shown. Unfortunately, the suggested generator dispatch does not always lead to feasible AC power flow solutions. Even when the AC solution is feasible, the inaccuracies of the DC power flow can lead to significant line overloads.

will develop and validate a basic model of a permanent magnet DC motor (Yaskawa Electric, Mini-series, Minertia of a permanent magnet DC motor, the field current is constant (i.e. a constant magnetic field). It can be shownEE443L: Intermediate Control Lab Lab2: Modeling a DC motor Introduction: In this lab we

Aalborg Universitet Supervisory Control of an Adaptive-Droop Regulated DC Microgrid with Battery Control of an Adaptive-Droop Regulated DC Microgrid with Battery Management Capability. I E E E, 2013 #12;1 Supervisory Control of an Adaptive-Droop Regulated DC Microgrid with Battery Management

The traditional electric vehicle DC motor drive system can not automatically weaken magnetic field. This paper designs DC motor drive system which control optimally the motor to meet the requirement. The study results show that: the drive system can ... Keywords: electric vehicles, DC motor, controller, optimal control

This paper presented the speed control of DC motor based on neural net and fuzzy logic. To bypass the difficulties caused by system constraints and modelling uncertainties of the speed control of DC motor a neural network approach for on-line speed control ... Keywords: DC motor, fuzzy logic, neural network, speed control

as max=-Vdc+Vrf+Vrf0, for a voltage on the dc electrode of Vdc, rf voltage of Vrf, and dc bias on the rf electrode of Vrf0. The dc current from the biased electrode must return to ground through surfaces other

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A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.

A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.

A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations. 15 figs.

Area Area (1974-1975) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: DC Resistivity Survey (Schlumberger Array) At Raft River Geothermal Area (1974-1975) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique DC Resistivity Survey (Schlumberger Array) Activity Date 1974 - 1975 Usefulness not indicated DOE-funding Unknown Exploration Basis Hydrogeologic study of the area Notes In 1975, the U.S. Geological Survey made 70 Schlumberger resistivity soundings in the Upper Raft River Valley and in parts of the Raft River Valley. These soundings complement the 79 soundings made previously in the Raft River Valley and bring the total number of soundings to 149. This work was done as part of a hydrogeologic study of the area. The location,

Plasmas have a beguiling way of getting students excited and interested in physics. We argue that plasmas can and should be incorporated into the undergraduate curriculum as both demonstrations and advanced investigations of electromagnetism and quantum effects. Our device, based on a direct current (DC) glow discharge tube, allows for a number of experiments into topics such as electrical breakdown, spectroscopy, magnetism, and electron temperature.

This report is a summary of discussions and conclusion from a workshop on the technology of superconducting DC transmission cables. The workshop was held at EPRI in Palo Alto, California on October 12, 13, and 14, 2005. The purpose of the meeting was to bring a small group of experts in technologies relevant to the development of such a cable and to enumerate potential issues, technical challenges, and a timetable for development. The first half of the workshop consisted of short technical presentations,...

An electronic tube and associated circuitry which is produced by dc plasma arc spraying techniques is described. The process is carried out in a single step automated process whereby both active and passive devices are produced at very low cost. The circuitry is extremely reliable and is capable of functioning in both high radiation and high temperature environments. The size of the electronic tubes produced are more than an order of magnitude smaller than conventional electronic tubes.

Available performance data for production motors are usually of marginal value to the electric vehicle designer. To provide at least a partial remedy to this situation, tests of typical dc propulsion motors and controllers were conducted as part of the DOE Electric Vehicle Program. The objectives of this program were to evaluate the differences in the performance of dc motors when operating with chopper-type controllers and when operating on direct current; and to gain an understanding of the interactions between the motor and the controller which cause these differences. Toward this end, motor-controller tests performed by the NASA Lewis Research Center provided some of the first published data that quantified motor efficiency variations for both ripple-free (straight dc) and chopper modes of operation. Test and analysis work at the University of Pittsburgh explored motor-controller relationships in greater depth. And to provide additional data, 3E Vehicles tested two small motors, both on a dynamometer and in a vehicle, and the Eaton Corporation tested larger motors, using sophisticated instrumentation and digital processing techniques. All the motors tested were direct-current types. Of the separately excited types, seven were series wound and two were shunt wound. One self-excited permanent magnet type was also tested. Four of the series wound motors used brush shifting to obtain good commutation. In almost all cases, controller limitations constrained the test envelope so that the full capability of the motors could not be explored.

Energy Challenge Two: The WeatherizeDC Campaign Energy Challenge Two: The WeatherizeDC Campaign Energy Challenge Two: The WeatherizeDC Campaign June 14, 2010 - 9:15am Addthis John Lippert In my quest to learn what other local groups are doing to help the environment and hopefully avoid reinventing the wheel, I attended a meeting of the Greenbelt Climate Action Network, a local chapter of the grassroots, nonprofit organization Chesapeake Climate Action Network. There I met two WeatherizeDC field organizers who described the work they are doing. Terrance and Heather explained that WeatherizeDC is a campaign of The DC Project, a nonprofit based in Washington, D.C., founded by former leaders of the Obama for America campaign around a mission to advance economic and environmental justice by creating clean energy career opportunities for

Solar Decathlon at Home in the D.C. Community Solar Decathlon at Home in the D.C. Community Solar Decathlon at Home in the D.C. Community Addthis A New Energy-Efficient Home in the D.C. Community 1 of 27 A New Energy-Efficient Home in the D.C. Community On December 4, 2012, the Empowerhouse team, along with partners and community members, completed the installation of a permanent, two-family home in Washington, D.C. The home was originally showcased as part of the U.S Department of Energy's Solar Decathlon 2011. Image: Sarah Gerrity Date taken: 2012-12-04 12:22 2 of 27 The house is located in the D.C. neighborhood of Deanwood, which is just 10 miles from the National Mall. By installing the house nearby, the team was able to minimize shipping costs, therefore reducing the house's carbon footprint. Image: Sarah Gerrity

3 Aerial view of Washington D.C. 3 Aerial view of Washington D.C. News From the D.C. Office Energy-Saving Office Equipment Part 2: Making the "Virtual Office" Real More on the DC Office efficiency up-grade: Lighting, Office Equipment: Part 1 Regular readers of the Center for Building Science News know that energy-efficient lighting and office equipment can have significant environmental and economic benefits. Previous articles ("Monitored Savings from Energy-Efficient Lighting in D.C. Office" [Spring 1997, p. 3] and "Energy-Saving Office equipment" [Summer 1997, p. 3]) discussed these features of Berkeley Lab's Washington, D.C. office. The D.C. office also serves as a demonstration site for telecommunications technologies, which have energy and environmental benefits of their own.

The upgrade of the Large Hadron Collider (LHC) experiments at CERN sets new challenges for the powering of the detectors. One of the powering schemes under study is based on DC-DC buck converters mounted on the front-end modules. The hard environmental conditions impose strict restrictions to the converters in terms of low volume, radiation and magnetic field tolerance. Furthermore, the noise emission of the switching converters must not affect the performance of the powered systems. A study of the sources and paths of noise of a synchronous buck converter has been made for identifying the critical parameters to reduce their emissions. As proof of principle, a converter was designed following the PCB layout considerations proposed and then used for powering a silicon strip module prototype for the ATLAS upgrade, in order to evaluate their compatibility.

DC/DC converter has a transformer having primary coils connected to an input side and secondary coils connected to an output side. Each primary coil connects a full-bridge circuit comprising two switches on two legs, the primary coil being connected between the switches on each leg, each full-bridge circuit being connected in parallel wherein each leg is disposed parallel to one another, and the secondary coils connected to a rectifying circuit. An outer loop control circuit that reduces ripple in a voltage reference has a first resistor connected in series with a second resistor connected in series with a first capacitor which are connected in parallel with a second capacitor. An inner loop control circuit that reduces ripple in a current reference has a third resistor connected in series with a fourth resistor connected in series with a third capacitor which are connected in parallel with a fourth capacitor.

A tunable femtosecond solid-state amplifier system that uses only 3 W of 488-nm argon-ion pump power has been demonstrated to deliver microjoule pulses at repetition rates up to 20 kHz, with a maximum pulse energy of 14 {mu}J obtained at 5 kHz. An all-solid-state, tunable, diode-pumped Cr:LiSrAlF{sub 6} regenerative amplifier has been demonstrated, for the first time to our knowledge, that amplifies femtosecond pulses to energies exceeding 1 {mu}J at up to a 16-kHz repetition rate.

During the third quarter of the Solar-MEC program, work continued on developing the computer model simulating the desiccant wheel behavior (Task 1) and assessing the performance of the regenerative heat exchange wheel (Task 3). This report specifically presents the results obtained using the computer model as an analytical tool to evaluate design and operating conditions to optimize the wheel's performance. It also contains evaluations of two different available heat transfer matrixes: the currently used aluminum honeycomb and a new product, a potentially less-expensive, corrugated aluminum material. The mathematical modeling and diagnostic evaluations and ways of improving the component and machine performance were identified and are described for both tasks.

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Abstract—A novel control scheme for improving the power efficiency of low-voltage dc–dc converters for battery-powered, portable applications is presented. In such applications, light-load efficiency is crucial for extending battery life, since mobile devices operate in stand-by mode for most of the time. The proposed technique adaptively reduces the inductor current ripple with decreasing load current while soft switching the converter to also reduce switching losses, thereby significantly improving light-load efficiency and therefore extending the operation life of battery-powered devices. A load-dependent, mode-hopping strategy is employed to maintain high efficiency over a wide load range. Hysteretic (sliding-mode) control with user programmable hysteresis is implemented to adaptively regulate the current ripple and therefore optimize conduction and switching losses. Experimental results show that for a 1-A, 5- to 1.8-V buck regulator, the proposed technique achieved 5 % power efficiency improvement (from 72 % to 77%) at 100 mA of load current and a 1.5% improvement (from 84 % to 85.5%) at 300 mA, which constitute light-load efficiency improvements, when compared to the best reported, state-of-the-art techniques. As a result, the battery life in a typical digital signalr processing microprocessor application is improved by 7%, which demonstrates the effectiveness of the proposed solution. Index Terms—Battery life, buck converter, dc–dc converter, efficiency, hysteretic control, sliding-mode control, soft switching, switching regulator.

923dc-45dc-45e5-b62b-3ca789517591 923dc-45dc-45e5-b62b-3ca789517591 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: Northern States Power Co - Minnesota Effective date: 2012/05/01 End date if known: Rate name: SMALL GENERAL TIME OF DAY SERVICE Low Wattage (A22) Sector: Commercial Description: Customer Charge per Month (Please see page 5-24.1) Available to any non-residential customer for single or three phase electric service supplied through one meter. DETERMINATION OF CUSTOMER BILLS Customer bills shall reflect energy charges (if applicable) based on customer's kWh usage, plus a customer charge (if applicable), plus demand charges (if applicable) based on customer's kW billing demand as defined. INTERIM RATE ADJUSTMENT A 4.49% Interim Rate Surcharge will be applied to rate components specified in the "Interim Rate Surcharge Rider." In addition, customer bills under this rate are subject to the following adjustments and/or charges. FUEL CLAUSE Bills are subject to the adjustments provided for in the Fuel Clause Rider. RESOURCE ADJUSTMENT Bills are subject to the adjustments provided for in the Conservation Improvement Program Adjustment Rider, the State Energy Policy Rate Rider, the Renewable Development Fund Rider, the Transmission Cost Recovery Rider, the Renewable Energy Standard Rider and the Mercury Cost Recovery Rider. ENVIRONMENTAL IMPROVEMENT RIDER Bills are subject to the adjustments provided for in the Environmental Improvement Rider.

The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. The original TFTR Hardwired Control System (HCS) with electromechanical relays was used for NSTX DC Power loop control and protection during NSTX operations. As part of the NSTX Upgrade, the HCS is being changed to a PLC-based system with the same control logic. This paper gives a description of the changeover to the new PLC-based system __________________________________________________

In this project one of the main objectives was the refinement of tools for the study of HVDC systems. The original software was prepared in project RP1964-2 (EL-4365) as power flow and stability program models for HVDC systems. In this project new modeling capabilities were added to both the power flow and stability models. Additionally, the HVDC specific model capabilities were integrated into a new program, termed the Standalone program, for use in the development and testing of HVDC models. This manual provides technical background for programmers and those interested in understanding, augmenting or transporting the dc models.

Previous researchers have analysed the forced commutated HVDC inverter and have concluded that it could be used to meet the reactive power at the inverter terminals. This investigation is a further technical appraisal involving a two terminal transmission scheme to a remote load with no ac generation at the load. Several possible inverter configurations are discussed. An electromagnetic transients program is used to model the system and simulate such aspects as start up, ac and dc faults and speed of response to voltage and frequency controls. The results indicate that such a scheme is indeed technically feasible and may be quite attractive from an economic and reliability point of view.

As the interface between fuel cells and the utility line, a self-commutated inverter is preferred to a line-commutated inverter because of its easy controllability. Using the gate turn off (GTO) thyristors, this inverter can have high efficiency and simple circuit configurations. This paper describes the design features and test results of the dc-to-ac power converter, which is principally composed of four-phase transistor chopper and 12-pulse GTO inverter, for a 50kW experimental fuel cell power system. Furthermore, new GTO inverter which improves the circuit efficiency is presented. Special emphasis is placed on a detailed analysis and evaluation of this GTO inverter.

3 Aerial view of Washington D.C. 3 Aerial view of Washington D.C. News From the D.C. Office Monitored Savings from Energy-Efficient Lighting in D.C. Office More on the DC Office efficiency up-grade: Office Equipment: Part 1, Part 2 Figure 1: Lighting energy use profile for a typical exterior office. Berkeley Lab's office in Washington, D.C. is located a few blocks from DOE headquarters, in a five-year-old office building constructed mainly for lease to Federal agencies and their contractors. Despite its recent vintage, the building's standard lighting specifications were far from today's best, cost-effective practice. In designing the build-out plans for offices and meeting rooms in our 7,500-square-foot suite, we wanted to showcase some of the energy-efficient lighting and office equipment developed for DOE's Building Technologies

Edison Revisited: Should we use DC Circuits for Lighting in Commercial Edison Revisited: Should we use DC Circuits for Lighting in Commercial Buildings? Speaker(s): Brinda Thomas Date: March 7, 2012 - 12:30pm Location: 90-3122 Seminar Host/Point of Contact: Chris Marnay This seminar summarizes work from a forthcoming Energy Policy paper and thoughts on future work to understand the economics of DC building circuits. We examined the economic feasibility of a general application of DC building circuits to operate commercial lighting systems. We compare light-emitting diodes (LEDs) and fluorescents that are powered by either a central DC power supply or traditional AC grid electricity, with and without solar photovoltaics (PV) and battery back-up. We find that there are limited life-cycle ownership cost and capital cost benefits of DC

This report describes and documents the construction and performance of a novel battery free backup power product, CoolAir (DC) based upon TACAS (Thermal Compressed Air Storage) technology and manufactured by Active Power of Austin, Texas. Comprised of compressed air tanks, thermal storage unit, high-speed air turbine, flywheel, and power electronics, the CoolAir DC is designed to deliver DC power to devices such as an uninterruptible power supply or adjustable speed drive while producing cool air during...

The past several years have seen renewed interest in the prospect of converting ac lines to dc operation interest spurred both by the ongoing need to make greater use of existing transmission assets and advances in HVDC converter technology. EPRI has sponsored two major studies dealing with the conversion prospect. The first, 8220Tools for Assessing Conversion of AC Power Transmission Lines to DC,(Product ID # 1020651) and the second, 8220Dc Capability of AC Transmission Lines,(Product ID #1013979). Cont...

Concepts of maximum power transfer of dc systems and associated ac voltage variations, particularly at inverter stations having low short-circuit ratios, have been extended to include various ac load models and an ac line in parallel with the dc line. The operating capabilities are shown to vary from those predicted from either a Thevenin ac source model or the corresponding short-circuit ratio. The study used an ac/dc load flow program.